diff --git a/ROADMAP.md b/ROADMAP.md
index f3e2b77..540ff44 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -15,6 +15,18 @@ requirements-file dependency change through the generated report and confirm
 that local risk buckets remain policy-review evidence rather than package
 safety verdicts.
 
+## v1.1: Input and Policy Semantics
+
+The v1.1 route is implementation-led: pin the real input support matrix,
+version policy and report contracts, make policy decision evidence explicit,
+then harden component identity canonicalization and same-input conflict
+diagnostics. The detailed acceptance gates live in
+[tools/sbom-diff-and-risk/docs/v1.1-input-and-policy-semantics.md](tools/sbom-diff-and-risk/docs/v1.1-input-and-policy-semantics.md).
+
+The tool remains in this monorepo. Repository extraction is deferred until
+real third-party adoption creates an independent release or maintenance
+boundary.
+
 ## Parked Directions
 
 - Parser-boundary fixtures, only when the before/after input and normalized
diff --git a/tools/sbom-diff-and-risk/README.md b/tools/sbom-diff-and-risk/README.md
index ecf9bfb..552e898 100644
--- a/tools/sbom-diff-and-risk/README.md
+++ b/tools/sbom-diff-and-risk/README.md
@@ -42,6 +42,8 @@ For a consumer-facing GitHub Actions example, see
 [docs/github-actions-consumer-example.md](docs/github-actions-consumer-example.md).
 For regenerating checked-in local example outputs, see
 [docs/example-artifact-regeneration.md](docs/example-artifact-regeneration.md).
+The v1.1 implementation sequence is fixed in
+[docs/v1.1-input-and-policy-semantics.md](docs/v1.1-input-and-policy-semantics.md).
 
 1. If you want to verify `sbom-diff-and-risk` itself, start with
    [docs/verification.md](docs/verification.md).
@@ -93,11 +95,14 @@ When a `purl` includes a version, the tool keeps the full value in `Component.pu
 
 ## Supported Formats
 
-- CycloneDX JSON
-- SPDX JSON
-- `requirements.txt`
-- `pyproject.toml` via PEP 621 `[project]` metadata
-- `pyproject.toml` dependency groups via PEP 735 `[dependency-groups]` with explicit selection
+- CycloneDX JSON, top-level component subset
+- SPDX JSON, top-level package subset
+- `requirements.txt`, conservative PEP 508 subset
+- `pyproject.toml`, PEP 621 arrays and explicitly selected PEP 735 groups
+
+See the test-backed [input format support matrix](docs/parser-boundaries.md)
+for the exact fields and unsupported constructs. A recognized container format
+does not imply full specification conformance.
 
 ## Risk Bucket Semantics
 
@@ -219,7 +224,7 @@ The checked-in [examples/sample-summary.json](examples/sample-summary.json) arti
 For CI dashboard, job-summary, and local-threshold examples, see [docs/summary-json-ci-cookbook.md](docs/summary-json-ci-cookbook.md).
 
 `--policy-json PATH` writes only policy-related JSON sections from the full
-report. It includes `policy_evaluation`, policy finding lists, `rule_catalog`,
+report. It includes `policy_schema`, `policy_evaluation`, policy finding lists, `rule_catalog`,
 and `summary.policy` when policy evaluation is applied. For CI job-summary
 examples, see
 [docs/policy-decision-ci-cookbook.md](docs/policy-decision-ci-cookbook.md).
diff --git a/tools/sbom-diff-and-risk/docs/parser-boundaries.md b/tools/sbom-diff-and-risk/docs/parser-boundaries.md
index 2d289c0..a91f307 100644
--- a/tools/sbom-diff-and-risk/docs/parser-boundaries.md
+++ b/tools/sbom-diff-and-risk/docs/parser-boundaries.md
@@ -1,10 +1,45 @@
-# Parser boundaries
+# Input format support matrix and parser boundaries
 
 `sbom-diff-and-risk` intentionally supports a conservative parser subset so local runs remain deterministic, auditable, and CI-friendly.
 
 The project does not try to emulate a package installer. When syntax would require resolver behavior, implicit includes, index lookups, or environment-specific side effects, the parser fails closed with an explicit error.
 
-## requirements.txt
+## Support matrix
+
+Every row below describes parser behavior implemented and covered by tests. A
+recognized container format does not imply full specification conformance.
+
+| Input | CLI format | Implemented subset | Not claimed |
+| --- | --- | --- | --- |
+| CycloneDX JSON | `cyclonedx-json` | Top-level `components`; component name, version, purl, bom-ref, type, first usable license, supplier/author, and selected external-reference URLs | CycloneDX schema validation, dependency graphs, services, vulnerabilities, compositions, or recursive nested components |
+| SPDX JSON | `spdx-json` | Top-level `packages`; package name, versionInfo, SPDXID, primary purpose, declared/concluded license, supplier/originator, purl external reference, and selected source URLs | SPDX schema validation, relationship graphs, files, snippets, annotations, or license analysis |
+| requirements file | `requirements-txt` | The PEP 508 requirement subset listed below, with comments and deterministic line continuation | pip installation semantics, includes, constraints, index configuration, hashes, URLs, VCS references, archives, or local paths |
+| `pyproject.toml` | `pyproject-toml` | PEP 621 dependency arrays and explicitly selected PEP 735 dependency groups, including local group includes | A general Python lockfile/parser, build backend interpretation, or Poetry/Hatch/PDM tool-specific tables |
+
+No XML SBOM, SPDX tag-value, YAML SBOM, package-lock, poetry.lock, uv.lock,
+or other lockfile parser is currently registered. Such formats are unsupported,
+not silently treated as one of the rows above.
+
+## CycloneDX JSON
+
+The parser requires a top-level JSON object with `bomFormat: CycloneDX`. It
+reads only the top-level `components` array. Each component requires `name`;
+all other normalized fields are optional.
+
+The parser does not currently constrain `specVersion` or validate the document
+against a CycloneDX schema. Acceptance therefore means the implemented fields
+were readable, not that the entire document is CycloneDX-conformant.
+
+## SPDX JSON
+
+The parser requires a top-level JSON object with a string `spdxVersion` and
+reads only the top-level `packages` array. Each package requires `name`.
+
+The parser does not currently constrain the SPDX version or validate the
+document against an SPDX schema. Relationships and file-level data do not
+affect component identity or policy decisions.
+
+## Requirements files
 
 `requirements.txt` is treated as a narrow manifest format, not as "everything pip can do in a file".
 
@@ -23,18 +58,19 @@ The project does not try to emulate a package installer. When syntax would requi
 
 When unsupported syntax appears, the parser raises `UnsupportedInputError` and the CLI returns exit code `2`.
 
-## pyproject.toml
+## `pyproject.toml`
 
 `pyproject.toml` support is also intentionally narrow:
 
 | Section | Status | Notes |
 | --- | --- | --- |
-| `[project.dependencies]` | Supported | Parsed by default |
-| `[project.optional-dependencies]` | Supported | Parsed by default and kept distinct from dependency groups |
+| `[project]` `dependencies` | Supported | Parsed by default as a PEP 508 string array |
+| `[project.optional-dependencies]` | Supported | Every declared optional group is parsed by default and kept distinct from dependency groups |
 | `[dependency-groups]` | Supported | Requires explicit `--pyproject-group <name>` selection |
 | `{ include-group = "name" }` inside dependency groups | Supported | Includes are resolved locally and deterministically |
+| PEP 508 direct references in supported arrays | Supported | Recorded as local manifest evidence; no URL is fetched by the parser |
 | Missing requested dependency group | Explicit error | Reported as `InputSelectionError` |
-| Poetry, Hatch, PDM, or other tool-specific dependency sections | Unsupported | Not parsed in v0.2 |
+| Poetry, Hatch, PDM, or other tool-specific dependency sections | Unsupported | Not parsed |
 
 Dependency groups are not merged automatically with `[project.optional-dependencies]`. They solve different problems and are kept separate on purpose.
 
diff --git a/tools/sbom-diff-and-risk/docs/policy-decision-explainability.md b/tools/sbom-diff-and-risk/docs/policy-decision-explainability.md
index 47550ac..a9379cf 100644
--- a/tools/sbom-diff-and-risk/docs/policy-decision-explainability.md
+++ b/tools/sbom-diff-and-risk/docs/policy-decision-explainability.md
@@ -27,6 +27,10 @@ policy findings.
 
 ## Field contract
 
+- `matched_rule_id`: Exact policy rule id that produced the decision.
+- `exact_evidence`: Stable object containing the compared component key,
+  finding bucket, configured threshold, and observed value. Non-applicable
+  members remain `null` rather than disappearing.
 - `decision_reason`: Stable reason code for the policy decision.
 - `policy_rule`: Policy rule id that produced the decision.
 - `severity_source`: Source of the active severity, such as `block_on`,
@@ -36,6 +40,11 @@ policy findings.
   decision, when applicable.
 - `observed_value`: Observed local value that was compared to the policy rule,
   when applicable.
+- `confidence_level`: Evidence source level for this decision:
+  `policy_matched`, `provenance_recorded`, or `scorecard_recorded`.
+
+`confidence_level` describes which recorded evidence the decision used. It is
+not a probability and does not express package safety.
 
 The full JSON report shape is documented in [report-schema.md](report-schema.md).
 Policy configuration fields and supported rules are documented in
@@ -47,7 +56,15 @@ A policy finding with:
 
 ```json
 {
+  "matched_rule_id": "max_added_packages",
   "decision_reason": "added_package_count_exceeded_threshold",
+  "exact_evidence": {
+    "component_key": null,
+    "finding_bucket": null,
+    "matched_threshold": 0,
+    "observed_value": 1
+  },
+  "confidence_level": "policy_matched",
   "policy_rule": "max_added_packages",
   "severity_source": "block_on",
   "matched_threshold": 0,
@@ -63,7 +80,15 @@ A policy finding with:
 
 ```json
 {
+  "matched_rule_id": "new_package",
   "decision_reason": "risk_finding_matched_policy_rule",
+  "exact_evidence": {
+    "component_key": "purl:pkg:pypi/example-package",
+    "finding_bucket": "new_package",
+    "matched_threshold": null,
+    "observed_value": "new_package"
+  },
+  "confidence_level": "policy_matched",
   "policy_rule": "new_package",
   "severity_source": "warn_on",
   "matched_threshold": null,
diff --git a/tools/sbom-diff-and-risk/docs/policy-schema.md b/tools/sbom-diff-and-risk/docs/policy-schema.md
index fed0f4e..71f4100 100644
--- a/tools/sbom-diff-and-risk/docs/policy-schema.md
+++ b/tools/sbom-diff-and-risk/docs/policy-schema.md
@@ -1,20 +1,31 @@
 # Policy schema
 
-`sbom-diff-and-risk` supports YAML-only policy schemas in versions `1`, `2`,
-and `3` for the local, provenance-aware, and optional Scorecard-aware policy
-flows described here.
+`sbom-diff-and-risk` identifies the serialized policy contract with:
+
+```yaml
+policy_schema: sbom-diff-risk.policy.v1
+```
+
+The separate integer `version` remains the policy capability level: `1` for
+local rules, `2` for provenance-aware rules, and `3` for optional
+Scorecard-aware rules. Keeping these concepts separate lets the serialized
+contract evolve without relabeling existing rule capability levels.
 
 The schema is intentionally conservative and fail-closed:
 
 - unknown rule ids are rejected
 - unknown top-level keys are rejected
+- unknown `policy_schema` values are rejected
 - invalid types are rejected
+- policies that omit `policy_schema` remain readable as v1.0-compatible input
+- normalized policy output always records `sbom-diff-risk.policy.v1`
 - version `1` remains the v0.2-compatible schema and existing v0.2 policies continue to work unchanged
 - version `2` adds provenance-aware gating for explicit PyPI enrichment evidence
 - version `3` adds optional Scorecard-aware gating for explicitly requested Scorecard enrichment
 
 ## Version 1 fields
 
+- `policy_schema: sbom-diff-risk.policy.v1`
 - `version: 1`
 - `block_on: [rule_id, ...]`
 - `warn_on: [rule_id, ...]`
@@ -113,6 +124,7 @@ see
 ## Version 1 example
 
 ```yaml
+policy_schema: sbom-diff-risk.policy.v1
 version: 1
 block_on:
   - unknown_license
@@ -130,6 +142,7 @@ ignore_rules:
 ## Version 2 example
 
 ```yaml
+policy_schema: sbom-diff-risk.policy.v1
 version: 2
 block_on:
   - provenance_required
@@ -147,6 +160,7 @@ allow_unattested_publishers:
 ## Version 3 example
 
 ```yaml
+policy_schema: sbom-diff-risk.policy.v1
 version: 3
 warn_on:
   - scorecard_below_threshold
diff --git a/tools/sbom-diff-and-risk/docs/policy-warning-reviewer-case.md b/tools/sbom-diff-and-risk/docs/policy-warning-reviewer-case.md
index aade426..ea3669e 100644
--- a/tools/sbom-diff-and-risk/docs/policy-warning-reviewer-case.md
+++ b/tools/sbom-diff-and-risk/docs/policy-warning-reviewer-case.md
@@ -30,6 +30,7 @@ Reference inputs and policy:
 The minimal policy is intentionally small:
 
 ```yaml
+policy_schema: sbom-diff-risk.policy.v1
 version: 1
 block_on:
   - unknown_license
diff --git a/tools/sbom-diff-and-risk/docs/report-schema.md b/tools/sbom-diff-and-risk/docs/report-schema.md
index f4f792d..86449a0 100644
--- a/tools/sbom-diff-and-risk/docs/report-schema.md
+++ b/tools/sbom-diff-and-risk/docs/report-schema.md
@@ -15,6 +15,7 @@ JSON reports currently use this top-level structure:
 
 | Field | Description |
 | --- | --- |
+| `report_schema` | Stable report contract identifier; currently `sbom-diff-risk.report.v1`. |
 | `summary` | Compact run summary for deterministic machine consumption. |
 | `evidence_confidence` | Highest evidence-confidence level represented by this report. |
 | `components` | Added, removed, and changed component records. |
@@ -53,6 +54,11 @@ These fields describe why a local policy rule produced a block, warning, or
 suppression. They are policy-decision metadata only; they are not dependency
 safety verdicts, CVE results, or proof that a package is safe or unsafe.
 
+- `matched_rule_id`: Exact policy rule id that produced the decision. The
+  legacy `rule_id` and `policy_rule` fields remain available in report v1.
+- `exact_evidence`: Structured local comparison evidence with
+  `component_key`, `finding_bucket`, `matched_threshold`, and
+  `observed_value`. Values remain `null` when that dimension does not apply.
 - `decision_reason`: Stable reason code for the policy decision, such as
   `risk_finding_matched_policy_rule`,
   `added_package_count_exceeded_threshold`, or
@@ -66,6 +72,9 @@ safety verdicts, CVE results, or proof that a package is safe or unsafe.
   decision, when applicable.
 - `observed_value`: Observed local value that was compared to the policy rule,
   when applicable.
+- `confidence_level`: Evidence level used for this decision. Local policy
+  matches use `policy_matched`; decisions based on recorded provenance or
+  Scorecard data use `provenance_recorded` or `scorecard_recorded`.
 
 Explanation fields appear only on policy finding objects. Risk findings in
 `risks` remain the analyzer's local heuristic findings and do not receive
@@ -80,6 +89,7 @@ consumer snippets, see
 The `--policy-json PATH` CLI option writes a policy-only JSON sidecar using the
 same policy-related sections from the full JSON report:
 
+- `policy_schema`, currently `sbom-diff-risk.policy.v1`
 - `policy_evaluation`
 - `blocking_findings`
 - `warning_findings`
@@ -170,6 +180,8 @@ stable for tests and downstream consumers.
 ## Stability notes
 
 - JSON reports are intended for machine consumption.
+- Consumers should select the contract using `report_schema` before relying on
+  required fields.
 - Golden samples lock important output shape for stable reviewer and CI expectations.
 - The schema is conservative and additive where possible.
 - Missing `summary.policy` means policy was not applied.
diff --git a/tools/sbom-diff-and-risk/docs/v1.1-input-and-policy-semantics.md b/tools/sbom-diff-and-risk/docs/v1.1-input-and-policy-semantics.md
new file mode 100644
index 0000000..5079241
--- /dev/null
+++ b/tools/sbom-diff-and-risk/docs/v1.1-input-and-policy-semantics.md
@@ -0,0 +1,90 @@
+# v1.1 technical route: Input and Policy Semantics
+
+v1.1 narrows ambiguity at the two boundaries that CI consumers depend on:
+what an input parser actually supports, and why a policy decision was emitted.
+It does not add another scientific-computing mini-project or move the tool out
+of this monorepo.
+
+## Delivery status
+
+| Contract | Current v1.1 status |
+| --- | --- |
+| Real input support matrix | Implemented in [parser-boundaries.md](parser-boundaries.md) from the registered parsers |
+| Policy schema identifier | Implemented as `sbom-diff-risk.policy.v1`; legacy policy files remain readable |
+| Report schema identifier and compatibility tests | Implemented as `sbom-diff-risk.report.v1` across checked-in full-report fixtures |
+| Per-decision rule, evidence, reason, and confidence | Implemented additively in report v1 policy finding objects |
+| Component identity canonicalization | Next implementation slice; target semantics are fixed below |
+
+## Component identity target
+
+The canonical identity record will expose these dimensions separately:
+
+- `ecosystem`: trimmed and normalized to a registered ecosystem identifier.
+- `package_name`: normalized with ecosystem-aware rules. PyPI names use PEP
+  503 normalization; other ecosystems require explicit test-backed rules.
+- `version`: trimmed but otherwise preserved as observed. The tool will not
+  infer semantic equivalence between unrelated version schemes.
+- `purl`: parsed and normalized when present, while retaining the observed purl
+  in component evidence for auditability.
+- `component_key`: versionless package identity used to align before and after
+  inputs. A version change remains a change, not an add plus remove.
+
+Identity authority remains `purl`, then `bom_ref`, then the normalized
+`(ecosystem, package_name)` coordinate. A parseable purl is authoritative for
+its ecosystem and package coordinate. Explicit metadata that disagrees with
+that coordinate is a conflict, not an alternative identity.
+
+Within one input:
+
+- two records with the same key and identical normalized metadata fail closed
+  as `duplicate_component`;
+- two records with the same key but different normalized metadata fail closed
+  as `conflicting_metadata`;
+- conflicting ecosystem, package name, or version information between a purl
+  and explicit fields also fails closed as `conflicting_metadata`;
+- metadata differences across the before and after inputs remain normal diff
+  evidence and do not become same-input conflicts.
+
+The next code slice should introduce a typed canonical identity object and
+diagnostic error codes before changing report presentation. Cross-format tests
+must cover CycloneDX to SPDX alignment, PyPI name normalization, versioned
+purls, exact duplicates, and conflicting metadata.
+
+## Policy and decision contract
+
+`policy_schema` identifies the serialized policy family. The existing integer
+`version` continues to select rule capabilities and remains compatible with
+v1.0 policy files.
+
+Every emitted policy finding includes:
+
+- `matched_rule_id` for the exact matching rule;
+- `exact_evidence` for the local values used in the comparison;
+- `decision_reason` as a stable machine-readable reason code;
+- `confidence_level` for the recorded evidence source.
+
+The legacy `rule_id`, `policy_rule`, `matched_threshold`, and `observed_value`
+fields remain in report schema v1. Consumers can migrate to the grouped fields
+without a flag day.
+
+## Compatibility gate
+
+Before v1.1 release:
+
+1. Every checked-in full JSON report must declare
+   `sbom-diff-risk.report.v1` and satisfy required-field/type tests.
+2. Every canonical policy example must declare
+   `sbom-diff-risk.policy.v1`; legacy omission remains a tested compatibility
+   path.
+3. Unknown policy schema identifiers must fail closed.
+4. Policy decisions in local, provenance, and Scorecard fixtures must expose
+   rule, evidence, reason, and confidence fields.
+5. Existing v1.0 fields remain readable for the lifetime of report schema v1.
+
+## Repository boundary
+
+`sbom-diff-and-risk` remains under `tools/` in this monorepo for v1.1. Naming
+friction alone is not a migration trigger. A separate repository should be
+considered only after real third-party adoption creates an independent release
+cadence, issue stream, or packaging boundary. Production PyPI publishing is a
+separate decision and is not implied by this route.
diff --git a/tools/sbom-diff-and-risk/examples/policy-decisions/fail.json b/tools/sbom-diff-and-risk/examples/policy-decisions/fail.json
index b4df6a0..a1c6d15 100644
--- a/tools/sbom-diff-and-risk/examples/policy-decisions/fail.json
+++ b/tools/sbom-diff-and-risk/examples/policy-decisions/fail.json
@@ -1,5 +1,6 @@
 {
   "example_type": "policy-decision-example",
+  "policy_schema": "sbom-diff-risk.policy.v1",
   "review_decision": "fail",
   "decision_source": "summary.policy",
   "summary": {
@@ -13,8 +14,16 @@
   "policy_findings": [
     {
       "rule_id": "max_added_packages",
+      "matched_rule_id": "max_added_packages",
       "level": "block",
       "decision_reason": "added_package_count_exceeded_threshold",
+      "exact_evidence": {
+        "component_key": null,
+        "finding_bucket": null,
+        "matched_threshold": 0,
+        "observed_value": 1
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "max_added_packages",
       "severity_source": "block_on",
       "matched_threshold": 0,
diff --git a/tools/sbom-diff-and-risk/examples/policy-decisions/pass.json b/tools/sbom-diff-and-risk/examples/policy-decisions/pass.json
index 64c8c84..853f749 100644
--- a/tools/sbom-diff-and-risk/examples/policy-decisions/pass.json
+++ b/tools/sbom-diff-and-risk/examples/policy-decisions/pass.json
@@ -1,5 +1,6 @@
 {
   "example_type": "policy-decision-example",
+  "policy_schema": "sbom-diff-risk.policy.v1",
   "review_decision": "pass",
   "decision_source": "summary.policy",
   "summary": {
diff --git a/tools/sbom-diff-and-risk/examples/policy-decisions/warn.json b/tools/sbom-diff-and-risk/examples/policy-decisions/warn.json
index b963f47..6c44f75 100644
--- a/tools/sbom-diff-and-risk/examples/policy-decisions/warn.json
+++ b/tools/sbom-diff-and-risk/examples/policy-decisions/warn.json
@@ -1,5 +1,6 @@
 {
   "example_type": "policy-decision-example",
+  "policy_schema": "sbom-diff-risk.policy.v1",
   "review_decision": "warn",
   "decision_source": "summary.policy",
   "summary": {
@@ -13,12 +14,21 @@
   "policy_findings": [
     {
       "rule_id": "new_package",
+      "matched_rule_id": "new_package",
       "level": "warn",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/urllib3",
+        "finding_bucket": "new_package",
+        "matched_threshold": null,
+        "observed_value": "new_package"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "new_package",
       "severity_source": "warn_on",
       "matched_threshold": null,
       "observed_value": "new_package",
+      "component_key": "purl:pkg:pypi/urllib3",
       "component_name": "urllib3"
     }
   ],
diff --git a/tools/sbom-diff-and-risk/examples/policy-minimal.yml b/tools/sbom-diff-and-risk/examples/policy-minimal.yml
index 0a858dd..73fdbaa 100644
--- a/tools/sbom-diff-and-risk/examples/policy-minimal.yml
+++ b/tools/sbom-diff-and-risk/examples/policy-minimal.yml
@@ -1,3 +1,4 @@
+policy_schema: sbom-diff-risk.policy.v1
 version: 1
 block_on:
   - unknown_license
diff --git a/tools/sbom-diff-and-risk/examples/policy-provenance-minimal.yml b/tools/sbom-diff-and-risk/examples/policy-provenance-minimal.yml
index 00458ba..f917f3f 100644
--- a/tools/sbom-diff-and-risk/examples/policy-provenance-minimal.yml
+++ b/tools/sbom-diff-and-risk/examples/policy-provenance-minimal.yml
@@ -1,4 +1,5 @@
 # Missing attestation remains a review signal, not proof of compromise.
+policy_schema: sbom-diff-risk.policy.v1
 version: 2
 warn_on:
   - missing_attestation
diff --git a/tools/sbom-diff-and-risk/examples/policy-provenance-strict.yml b/tools/sbom-diff-and-risk/examples/policy-provenance-strict.yml
index 9bf25e6..8e9e4c1 100644
--- a/tools/sbom-diff-and-risk/examples/policy-provenance-strict.yml
+++ b/tools/sbom-diff-and-risk/examples/policy-provenance-strict.yml
@@ -1,4 +1,5 @@
 # Explicit provenance requirements for enriched PyPI evidence.
+policy_schema: sbom-diff-risk.policy.v1
 version: 2
 block_on:
   - provenance_required
diff --git a/tools/sbom-diff-and-risk/examples/policy-scorecard-minimal.yml b/tools/sbom-diff-and-risk/examples/policy-scorecard-minimal.yml
index 0eb6f91..67511ce 100644
--- a/tools/sbom-diff-and-risk/examples/policy-scorecard-minimal.yml
+++ b/tools/sbom-diff-and-risk/examples/policy-scorecard-minimal.yml
@@ -1,3 +1,4 @@
+policy_schema: sbom-diff-risk.policy.v1
 version: 3
 warn_on:
   - scorecard_below_threshold
diff --git a/tools/sbom-diff-and-risk/examples/policy-strict.yml b/tools/sbom-diff-and-risk/examples/policy-strict.yml
index 9ebe01c..443e97c 100644
--- a/tools/sbom-diff-and-risk/examples/policy-strict.yml
+++ b/tools/sbom-diff-and-risk/examples/policy-strict.yml
@@ -1,3 +1,4 @@
+policy_schema: sbom-diff-risk.policy.v1
 version: 1
 block_on:
   - unknown_license
diff --git a/tools/sbom-diff-and-risk/examples/sample-policy-fail-report.json b/tools/sbom-diff-and-risk/examples/sample-policy-fail-report.json
index a88a064..cd77878 100644
--- a/tools/sbom-diff-and-risk/examples/sample-policy-fail-report.json
+++ b/tools/sbom-diff-and-risk/examples/sample-policy-fail-report.json
@@ -1,4 +1,5 @@
 {
+  "report_schema": "sbom-diff-risk.report.v1",
   "summary": {
     "added": 1,
     "removed": 0,
@@ -312,6 +313,7 @@
     "applied": true,
     "policy_path": "examples/policy-strict.yml",
     "effective_policy": {
+      "policy_schema": "sbom-diff-risk.policy.v1",
       "version": 1,
       "block_on": [
         "unknown_license",
@@ -335,9 +337,17 @@
     "blocking_violations": [
       {
         "rule_id": "max_added_packages",
+        "matched_rule_id": "max_added_packages",
         "level": "block",
         "message": "Added package count 1 exceeds max_added_packages=0.",
         "decision_reason": "added_package_count_exceeded_threshold",
+        "exact_evidence": {
+          "component_key": null,
+          "finding_bucket": null,
+          "matched_threshold": 0,
+          "observed_value": 1
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "max_added_packages",
         "severity_source": "block_on",
         "matched_threshold": 0,
@@ -349,9 +359,17 @@
       },
       {
         "rule_id": "stale_package",
+        "matched_rule_id": "stale_package",
         "level": "block",
         "message": "stale_package was not evaluated because enrichment mode is disabled.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/requests",
+          "finding_bucket": "not_evaluated",
+          "matched_threshold": null,
+          "observed_value": "not_evaluated"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "stale_package",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -363,9 +381,17 @@
       },
       {
         "rule_id": "stale_package",
+        "matched_rule_id": "stale_package",
         "level": "block",
         "message": "stale_package was not evaluated because enrichment mode is disabled.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/urllib3",
+          "finding_bucket": "not_evaluated",
+          "matched_threshold": null,
+          "observed_value": "not_evaluated"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "stale_package",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -379,9 +405,17 @@
     "warning_violations": [
       {
         "rule_id": "new_package",
+        "matched_rule_id": "new_package",
         "level": "warn",
         "message": "Component was not present in the before input.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/urllib3",
+          "finding_bucket": "new_package",
+          "matched_threshold": null,
+          "observed_value": "new_package"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "new_package",
         "severity_source": "warn_on",
         "matched_threshold": null,
@@ -404,9 +438,17 @@
   "blocking_findings": [
     {
       "rule_id": "max_added_packages",
+      "matched_rule_id": "max_added_packages",
       "level": "block",
       "message": "Added package count 1 exceeds max_added_packages=0.",
       "decision_reason": "added_package_count_exceeded_threshold",
+      "exact_evidence": {
+        "component_key": null,
+        "finding_bucket": null,
+        "matched_threshold": 0,
+        "observed_value": 1
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "max_added_packages",
       "severity_source": "block_on",
       "matched_threshold": 0,
@@ -418,9 +460,17 @@
     },
     {
       "rule_id": "stale_package",
+      "matched_rule_id": "stale_package",
       "level": "block",
       "message": "stale_package was not evaluated because enrichment mode is disabled.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/requests",
+        "finding_bucket": "not_evaluated",
+        "matched_threshold": null,
+        "observed_value": "not_evaluated"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "stale_package",
       "severity_source": "block_on",
       "matched_threshold": null,
@@ -432,9 +482,17 @@
     },
     {
       "rule_id": "stale_package",
+      "matched_rule_id": "stale_package",
       "level": "block",
       "message": "stale_package was not evaluated because enrichment mode is disabled.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/urllib3",
+        "finding_bucket": "not_evaluated",
+        "matched_threshold": null,
+        "observed_value": "not_evaluated"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "stale_package",
       "severity_source": "block_on",
       "matched_threshold": null,
@@ -448,9 +506,17 @@
   "warning_findings": [
     {
       "rule_id": "new_package",
+      "matched_rule_id": "new_package",
       "level": "warn",
       "message": "Component was not present in the before input.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/urllib3",
+        "finding_bucket": "new_package",
+        "matched_threshold": null,
+        "observed_value": "new_package"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "new_package",
       "severity_source": "warn_on",
       "matched_threshold": null,
@@ -613,6 +679,7 @@
       "applied": true,
       "policy_path": "examples/policy-strict.yml",
       "effective_policy": {
+        "policy_schema": "sbom-diff-risk.policy.v1",
         "version": 1,
         "block_on": [
           "unknown_license",
@@ -636,9 +703,17 @@
       "blocking_violations": [
         {
           "rule_id": "max_added_packages",
+          "matched_rule_id": "max_added_packages",
           "level": "block",
           "message": "Added package count 1 exceeds max_added_packages=0.",
           "decision_reason": "added_package_count_exceeded_threshold",
+          "exact_evidence": {
+            "component_key": null,
+            "finding_bucket": null,
+            "matched_threshold": 0,
+            "observed_value": 1
+          },
+          "confidence_level": "policy_matched",
           "policy_rule": "max_added_packages",
           "severity_source": "block_on",
           "matched_threshold": 0,
@@ -650,9 +725,17 @@
         },
         {
           "rule_id": "stale_package",
+          "matched_rule_id": "stale_package",
           "level": "block",
           "message": "stale_package was not evaluated because enrichment mode is disabled.",
           "decision_reason": "risk_finding_matched_policy_rule",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/requests",
+            "finding_bucket": "not_evaluated",
+            "matched_threshold": null,
+            "observed_value": "not_evaluated"
+          },
+          "confidence_level": "policy_matched",
           "policy_rule": "stale_package",
           "severity_source": "block_on",
           "matched_threshold": null,
@@ -664,9 +747,17 @@
         },
         {
           "rule_id": "stale_package",
+          "matched_rule_id": "stale_package",
           "level": "block",
           "message": "stale_package was not evaluated because enrichment mode is disabled.",
           "decision_reason": "risk_finding_matched_policy_rule",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/urllib3",
+            "finding_bucket": "not_evaluated",
+            "matched_threshold": null,
+            "observed_value": "not_evaluated"
+          },
+          "confidence_level": "policy_matched",
           "policy_rule": "stale_package",
           "severity_source": "block_on",
           "matched_threshold": null,
@@ -680,9 +771,17 @@
       "warning_violations": [
         {
           "rule_id": "new_package",
+          "matched_rule_id": "new_package",
           "level": "warn",
           "message": "Component was not present in the before input.",
           "decision_reason": "risk_finding_matched_policy_rule",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/urllib3",
+            "finding_bucket": "new_package",
+            "matched_threshold": null,
+            "observed_value": "new_package"
+          },
+          "confidence_level": "policy_matched",
           "policy_rule": "new_package",
           "severity_source": "warn_on",
           "matched_threshold": null,
diff --git a/tools/sbom-diff-and-risk/examples/sample-policy-warn-report.json b/tools/sbom-diff-and-risk/examples/sample-policy-warn-report.json
index e790ee7..0dc2a55 100644
--- a/tools/sbom-diff-and-risk/examples/sample-policy-warn-report.json
+++ b/tools/sbom-diff-and-risk/examples/sample-policy-warn-report.json
@@ -1,4 +1,5 @@
 {
+  "report_schema": "sbom-diff-risk.report.v1",
   "summary": {
     "added": 1,
     "removed": 0,
@@ -312,6 +313,7 @@
     "applied": true,
     "policy_path": "examples/policy-minimal.yml",
     "effective_policy": {
+      "policy_schema": "sbom-diff-risk.policy.v1",
       "version": 1,
       "block_on": [
         "unknown_license"
@@ -327,9 +329,17 @@
     "warning_violations": [
       {
         "rule_id": "new_package",
+        "matched_rule_id": "new_package",
         "level": "warn",
         "message": "Component was not present in the before input.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/urllib3",
+          "finding_bucket": "new_package",
+          "matched_threshold": null,
+          "observed_value": "new_package"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "new_package",
         "severity_source": "warn_on",
         "matched_threshold": null,
@@ -353,9 +363,17 @@
   "warning_findings": [
     {
       "rule_id": "new_package",
+      "matched_rule_id": "new_package",
       "level": "warn",
       "message": "Component was not present in the before input.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/urllib3",
+        "finding_bucket": "new_package",
+        "matched_threshold": null,
+        "observed_value": "new_package"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "new_package",
       "severity_source": "warn_on",
       "matched_threshold": null,
@@ -518,6 +536,7 @@
       "applied": true,
       "policy_path": "examples/policy-minimal.yml",
       "effective_policy": {
+        "policy_schema": "sbom-diff-risk.policy.v1",
         "version": 1,
         "block_on": [
           "unknown_license"
@@ -533,9 +552,17 @@
       "warning_violations": [
         {
           "rule_id": "new_package",
+          "matched_rule_id": "new_package",
           "level": "warn",
           "message": "Component was not present in the before input.",
           "decision_reason": "risk_finding_matched_policy_rule",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/urllib3",
+            "finding_bucket": "new_package",
+            "matched_threshold": null,
+            "observed_value": "new_package"
+          },
+          "confidence_level": "policy_matched",
           "policy_rule": "new_package",
           "severity_source": "warn_on",
           "matched_threshold": null,
diff --git a/tools/sbom-diff-and-risk/examples/sample-policy.json b/tools/sbom-diff-and-risk/examples/sample-policy.json
index 66c6d67..15a2239 100644
--- a/tools/sbom-diff-and-risk/examples/sample-policy.json
+++ b/tools/sbom-diff-and-risk/examples/sample-policy.json
@@ -1,8 +1,10 @@
 {
+  "policy_schema": "sbom-diff-risk.policy.v1",
   "policy_evaluation": {
     "applied": true,
     "policy_path": "examples/policy-strict.yml",
     "effective_policy": {
+      "policy_schema": "sbom-diff-risk.policy.v1",
       "version": 1,
       "block_on": [
         "unknown_license",
@@ -26,9 +28,17 @@
     "blocking_violations": [
       {
         "rule_id": "max_added_packages",
+        "matched_rule_id": "max_added_packages",
         "level": "block",
         "message": "Added package count 1 exceeds max_added_packages=0.",
         "decision_reason": "added_package_count_exceeded_threshold",
+        "exact_evidence": {
+          "component_key": null,
+          "finding_bucket": null,
+          "matched_threshold": 0,
+          "observed_value": 1
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "max_added_packages",
         "severity_source": "block_on",
         "matched_threshold": 0,
@@ -40,9 +50,17 @@
       },
       {
         "rule_id": "stale_package",
+        "matched_rule_id": "stale_package",
         "level": "block",
         "message": "stale_package was not evaluated because enrichment mode is disabled.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/requests",
+          "finding_bucket": "not_evaluated",
+          "matched_threshold": null,
+          "observed_value": "not_evaluated"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "stale_package",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -54,9 +72,17 @@
       },
       {
         "rule_id": "stale_package",
+        "matched_rule_id": "stale_package",
         "level": "block",
         "message": "stale_package was not evaluated because enrichment mode is disabled.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/urllib3",
+          "finding_bucket": "not_evaluated",
+          "matched_threshold": null,
+          "observed_value": "not_evaluated"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "stale_package",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -70,9 +96,17 @@
     "warning_violations": [
       {
         "rule_id": "new_package",
+        "matched_rule_id": "new_package",
         "level": "warn",
         "message": "Component was not present in the before input.",
         "decision_reason": "risk_finding_matched_policy_rule",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/urllib3",
+          "finding_bucket": "new_package",
+          "matched_threshold": null,
+          "observed_value": "new_package"
+        },
+        "confidence_level": "policy_matched",
         "policy_rule": "new_package",
         "severity_source": "warn_on",
         "matched_threshold": null,
@@ -95,9 +129,17 @@
   "blocking_findings": [
     {
       "rule_id": "max_added_packages",
+      "matched_rule_id": "max_added_packages",
       "level": "block",
       "message": "Added package count 1 exceeds max_added_packages=0.",
       "decision_reason": "added_package_count_exceeded_threshold",
+      "exact_evidence": {
+        "component_key": null,
+        "finding_bucket": null,
+        "matched_threshold": 0,
+        "observed_value": 1
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "max_added_packages",
       "severity_source": "block_on",
       "matched_threshold": 0,
@@ -109,9 +151,17 @@
     },
     {
       "rule_id": "stale_package",
+      "matched_rule_id": "stale_package",
       "level": "block",
       "message": "stale_package was not evaluated because enrichment mode is disabled.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/requests",
+        "finding_bucket": "not_evaluated",
+        "matched_threshold": null,
+        "observed_value": "not_evaluated"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "stale_package",
       "severity_source": "block_on",
       "matched_threshold": null,
@@ -123,9 +173,17 @@
     },
     {
       "rule_id": "stale_package",
+      "matched_rule_id": "stale_package",
       "level": "block",
       "message": "stale_package was not evaluated because enrichment mode is disabled.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/urllib3",
+        "finding_bucket": "not_evaluated",
+        "matched_threshold": null,
+        "observed_value": "not_evaluated"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "stale_package",
       "severity_source": "block_on",
       "matched_threshold": null,
@@ -139,9 +197,17 @@
   "warning_findings": [
     {
       "rule_id": "new_package",
+      "matched_rule_id": "new_package",
       "level": "warn",
       "message": "Component was not present in the before input.",
       "decision_reason": "risk_finding_matched_policy_rule",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/urllib3",
+        "finding_bucket": "new_package",
+        "matched_threshold": null,
+        "observed_value": "new_package"
+      },
+      "confidence_level": "policy_matched",
       "policy_rule": "new_package",
       "severity_source": "warn_on",
       "matched_threshold": null,
diff --git a/tools/sbom-diff-and-risk/examples/sample-provenance-report.json b/tools/sbom-diff-and-risk/examples/sample-provenance-report.json
index 4ad94bb..26b613d 100644
--- a/tools/sbom-diff-and-risk/examples/sample-provenance-report.json
+++ b/tools/sbom-diff-and-risk/examples/sample-provenance-report.json
@@ -1,4 +1,5 @@
 {
+  "report_schema": "sbom-diff-risk.report.v1",
   "summary": {
     "added": 2,
     "removed": 0,
@@ -372,6 +373,7 @@
     "applied": true,
     "policy_path": "examples/policy-provenance-strict.yml",
     "effective_policy": {
+      "policy_schema": "sbom-diff-risk.policy.v1",
       "version": 2,
       "block_on": [
         "provenance_required",
@@ -393,9 +395,17 @@
     "blocking_violations": [
       {
         "rule_id": "provenance_required",
+        "matched_rule_id": "provenance_required",
         "level": "block",
         "message": "Provenance is required for new package, but no attestations were published for this PyPI package.",
         "decision_reason": "required_provenance_not_satisfied",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/mystery-lib",
+          "finding_bucket": null,
+          "matched_threshold": null,
+          "observed_value": "attestation_missing"
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "provenance_required",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -407,9 +417,21 @@
       },
       {
         "rule_id": "unverified_provenance",
+        "matched_rule_id": "unverified_provenance",
         "level": "block",
         "message": "PyPI attestations were present, but publisher kinds manual upload did not match allow_provenance_publishers=github actions.",
         "decision_reason": "provenance_publisher_not_verified",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/legacy-lib",
+          "finding_bucket": null,
+          "matched_threshold": [
+            "github actions"
+          ],
+          "observed_value": [
+            "manual upload"
+          ]
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "unverified_provenance",
         "severity_source": "block_on",
         "matched_threshold": [
@@ -427,9 +449,17 @@
     "warning_violations": [
       {
         "rule_id": "missing_attestation",
+        "matched_rule_id": "missing_attestation",
         "level": "warn",
         "message": "PyPI release metadata was fetched, but no attestations were published for this package release.",
         "decision_reason": "attestation_not_published",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/mystery-lib",
+          "finding_bucket": null,
+          "matched_threshold": null,
+          "observed_value": false
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "missing_attestation",
         "severity_source": "warn_on",
         "matched_threshold": null,
@@ -452,9 +482,17 @@
   "blocking_findings": [
     {
       "rule_id": "provenance_required",
+      "matched_rule_id": "provenance_required",
       "level": "block",
       "message": "Provenance is required for new package, but no attestations were published for this PyPI package.",
       "decision_reason": "required_provenance_not_satisfied",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/mystery-lib",
+        "finding_bucket": null,
+        "matched_threshold": null,
+        "observed_value": "attestation_missing"
+      },
+      "confidence_level": "provenance_recorded",
       "policy_rule": "provenance_required",
       "severity_source": "block_on",
       "matched_threshold": null,
@@ -466,9 +504,21 @@
     },
     {
       "rule_id": "unverified_provenance",
+      "matched_rule_id": "unverified_provenance",
       "level": "block",
       "message": "PyPI attestations were present, but publisher kinds manual upload did not match allow_provenance_publishers=github actions.",
       "decision_reason": "provenance_publisher_not_verified",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/legacy-lib",
+        "finding_bucket": null,
+        "matched_threshold": [
+          "github actions"
+        ],
+        "observed_value": [
+          "manual upload"
+        ]
+      },
+      "confidence_level": "provenance_recorded",
       "policy_rule": "unverified_provenance",
       "severity_source": "block_on",
       "matched_threshold": [
@@ -486,9 +536,17 @@
   "warning_findings": [
     {
       "rule_id": "missing_attestation",
+      "matched_rule_id": "missing_attestation",
       "level": "warn",
       "message": "PyPI release metadata was fetched, but no attestations were published for this package release.",
       "decision_reason": "attestation_not_published",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/mystery-lib",
+        "finding_bucket": null,
+        "matched_threshold": null,
+        "observed_value": false
+      },
+      "confidence_level": "provenance_recorded",
       "policy_rule": "missing_attestation",
       "severity_source": "warn_on",
       "matched_threshold": null,
@@ -669,6 +727,7 @@
       "applied": true,
       "policy_path": "examples/policy-provenance-strict.yml",
       "effective_policy": {
+        "policy_schema": "sbom-diff-risk.policy.v1",
         "version": 2,
         "block_on": [
           "provenance_required",
@@ -690,9 +749,17 @@
       "blocking_violations": [
         {
           "rule_id": "provenance_required",
+          "matched_rule_id": "provenance_required",
           "level": "block",
           "message": "Provenance is required for new package, but no attestations were published for this PyPI package.",
           "decision_reason": "required_provenance_not_satisfied",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/mystery-lib",
+            "finding_bucket": null,
+            "matched_threshold": null,
+            "observed_value": "attestation_missing"
+          },
+          "confidence_level": "provenance_recorded",
           "policy_rule": "provenance_required",
           "severity_source": "block_on",
           "matched_threshold": null,
@@ -704,9 +771,21 @@
         },
         {
           "rule_id": "unverified_provenance",
+          "matched_rule_id": "unverified_provenance",
           "level": "block",
           "message": "PyPI attestations were present, but publisher kinds manual upload did not match allow_provenance_publishers=github actions.",
           "decision_reason": "provenance_publisher_not_verified",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/legacy-lib",
+            "finding_bucket": null,
+            "matched_threshold": [
+              "github actions"
+            ],
+            "observed_value": [
+              "manual upload"
+            ]
+          },
+          "confidence_level": "provenance_recorded",
           "policy_rule": "unverified_provenance",
           "severity_source": "block_on",
           "matched_threshold": [
@@ -724,9 +803,17 @@
       "warning_violations": [
         {
           "rule_id": "missing_attestation",
+          "matched_rule_id": "missing_attestation",
           "level": "warn",
           "message": "PyPI release metadata was fetched, but no attestations were published for this package release.",
           "decision_reason": "attestation_not_published",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/mystery-lib",
+            "finding_bucket": null,
+            "matched_threshold": null,
+            "observed_value": false
+          },
+          "confidence_level": "provenance_recorded",
           "policy_rule": "missing_attestation",
           "severity_source": "warn_on",
           "matched_threshold": null,
@@ -790,9 +877,17 @@
     "blocking": [
       {
         "rule_id": "provenance_required",
+        "matched_rule_id": "provenance_required",
         "level": "block",
         "message": "Provenance is required for new package, but no attestations were published for this PyPI package.",
         "decision_reason": "required_provenance_not_satisfied",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/mystery-lib",
+          "finding_bucket": null,
+          "matched_threshold": null,
+          "observed_value": "attestation_missing"
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "provenance_required",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -804,9 +899,21 @@
       },
       {
         "rule_id": "unverified_provenance",
+        "matched_rule_id": "unverified_provenance",
         "level": "block",
         "message": "PyPI attestations were present, but publisher kinds manual upload did not match allow_provenance_publishers=github actions.",
         "decision_reason": "provenance_publisher_not_verified",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/legacy-lib",
+          "finding_bucket": null,
+          "matched_threshold": [
+            "github actions"
+          ],
+          "observed_value": [
+            "manual upload"
+          ]
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "unverified_provenance",
         "severity_source": "block_on",
         "matched_threshold": [
@@ -824,9 +931,17 @@
     "warning": [
       {
         "rule_id": "missing_attestation",
+        "matched_rule_id": "missing_attestation",
         "level": "warn",
         "message": "PyPI release metadata was fetched, but no attestations were published for this package release.",
         "decision_reason": "attestation_not_published",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/mystery-lib",
+          "finding_bucket": null,
+          "matched_threshold": null,
+          "observed_value": false
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "missing_attestation",
         "severity_source": "warn_on",
         "matched_threshold": null,
@@ -857,9 +972,17 @@
     "blocking": [
       {
         "rule_id": "provenance_required",
+        "matched_rule_id": "provenance_required",
         "level": "block",
         "message": "Provenance is required for new package, but no attestations were published for this PyPI package.",
         "decision_reason": "required_provenance_not_satisfied",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/mystery-lib",
+          "finding_bucket": null,
+          "matched_threshold": null,
+          "observed_value": "attestation_missing"
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "provenance_required",
         "severity_source": "block_on",
         "matched_threshold": null,
@@ -871,9 +994,21 @@
       },
       {
         "rule_id": "unverified_provenance",
+        "matched_rule_id": "unverified_provenance",
         "level": "block",
         "message": "PyPI attestations were present, but publisher kinds manual upload did not match allow_provenance_publishers=github actions.",
         "decision_reason": "provenance_publisher_not_verified",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/legacy-lib",
+          "finding_bucket": null,
+          "matched_threshold": [
+            "github actions"
+          ],
+          "observed_value": [
+            "manual upload"
+          ]
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "unverified_provenance",
         "severity_source": "block_on",
         "matched_threshold": [
@@ -891,9 +1026,17 @@
     "warning": [
       {
         "rule_id": "missing_attestation",
+        "matched_rule_id": "missing_attestation",
         "level": "warn",
         "message": "PyPI release metadata was fetched, but no attestations were published for this package release.",
         "decision_reason": "attestation_not_published",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/mystery-lib",
+          "finding_bucket": null,
+          "matched_threshold": null,
+          "observed_value": false
+        },
+        "confidence_level": "provenance_recorded",
         "policy_rule": "missing_attestation",
         "severity_source": "warn_on",
         "matched_threshold": null,
diff --git a/tools/sbom-diff-and-risk/examples/sample-report.json b/tools/sbom-diff-and-risk/examples/sample-report.json
index 5f9caf6..6dd2971 100644
--- a/tools/sbom-diff-and-risk/examples/sample-report.json
+++ b/tools/sbom-diff-and-risk/examples/sample-report.json
@@ -1,4 +1,5 @@
 {
+  "report_schema": "sbom-diff-risk.report.v1",
   "summary": {
     "added": 1,
     "removed": 0,
diff --git a/tools/sbom-diff-and-risk/examples/sample-requirements-report.json b/tools/sbom-diff-and-risk/examples/sample-requirements-report.json
index c0d4ca6..36b5b1c 100644
--- a/tools/sbom-diff-and-risk/examples/sample-requirements-report.json
+++ b/tools/sbom-diff-and-risk/examples/sample-requirements-report.json
@@ -1,4 +1,5 @@
 {
+  "report_schema": "sbom-diff-risk.report.v1",
   "summary": {
     "added": 1,
     "removed": 0,
diff --git a/tools/sbom-diff-and-risk/examples/sample-scorecard-report.json b/tools/sbom-diff-and-risk/examples/sample-scorecard-report.json
index f70e4df..d65ab08 100644
--- a/tools/sbom-diff-and-risk/examples/sample-scorecard-report.json
+++ b/tools/sbom-diff-and-risk/examples/sample-scorecard-report.json
@@ -1,4 +1,5 @@
 {
+  "report_schema": "sbom-diff-risk.report.v1",
   "summary": {
     "added": 2,
     "removed": 0,
@@ -286,6 +287,7 @@
     "applied": true,
     "policy_path": "examples/policy-scorecard-minimal.yml",
     "effective_policy": {
+      "policy_schema": "sbom-diff-risk.policy.v1",
       "version": 3,
       "block_on": [],
       "warn_on": [
@@ -304,9 +306,17 @@
     "warning_violations": [
       {
         "rule_id": "scorecard_below_threshold",
+        "matched_rule_id": "scorecard_below_threshold",
         "level": "warn",
         "message": "Scorecard score 6.0 is below minimum_scorecard_score=7.0 for repository github.com/psf/requests.",
         "decision_reason": "scorecard_score_below_threshold",
+        "exact_evidence": {
+          "component_key": "purl:pkg:pypi/requests",
+          "finding_bucket": null,
+          "matched_threshold": 7.0,
+          "observed_value": 6.0
+        },
+        "confidence_level": "scorecard_recorded",
         "policy_rule": "scorecard_below_threshold",
         "severity_source": "warn_on",
         "matched_threshold": 7.0,
@@ -330,9 +340,17 @@
   "warning_findings": [
     {
       "rule_id": "scorecard_below_threshold",
+      "matched_rule_id": "scorecard_below_threshold",
       "level": "warn",
       "message": "Scorecard score 6.0 is below minimum_scorecard_score=7.0 for repository github.com/psf/requests.",
       "decision_reason": "scorecard_score_below_threshold",
+      "exact_evidence": {
+        "component_key": "purl:pkg:pypi/requests",
+        "finding_bucket": null,
+        "matched_threshold": 7.0,
+        "observed_value": 6.0
+      },
+      "confidence_level": "scorecard_recorded",
       "policy_rule": "scorecard_below_threshold",
       "severity_source": "warn_on",
       "matched_threshold": 7.0,
@@ -535,6 +553,7 @@
       "applied": true,
       "policy_path": "examples/policy-scorecard-minimal.yml",
       "effective_policy": {
+        "policy_schema": "sbom-diff-risk.policy.v1",
         "version": 3,
         "block_on": [],
         "warn_on": [
@@ -553,9 +572,17 @@
       "warning_violations": [
         {
           "rule_id": "scorecard_below_threshold",
+          "matched_rule_id": "scorecard_below_threshold",
           "level": "warn",
           "message": "Scorecard score 6.0 is below minimum_scorecard_score=7.0 for repository github.com/psf/requests.",
           "decision_reason": "scorecard_score_below_threshold",
+          "exact_evidence": {
+            "component_key": "purl:pkg:pypi/requests",
+            "finding_bucket": null,
+            "matched_threshold": 7.0,
+            "observed_value": 6.0
+          },
+          "confidence_level": "scorecard_recorded",
           "policy_rule": "scorecard_below_threshold",
           "severity_source": "warn_on",
           "matched_threshold": 7.0,
diff --git a/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_evaluator.py b/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_evaluator.py
index 9f5cd99..598d51c 100644
--- a/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_evaluator.py
+++ b/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_evaluator.py
@@ -4,7 +4,15 @@
 from urllib.parse import urlparse
 
 from .diffing import component_key
-from .models import Component, ComponentChange, ProvenanceStatus, RiskBucket, RiskFinding, ScorecardStatus
+from .models import (
+    Component,
+    ComponentChange,
+    EvidenceConfidence,
+    ProvenanceStatus,
+    RiskBucket,
+    RiskFinding,
+    ScorecardStatus,
+)
 from .policy_models import PolicyConfig, PolicyEvaluation, PolicyLevel, PolicyViolation
 
 
@@ -93,6 +101,11 @@ def evaluate_policy(
                     observed_value="unavailable",
                     component_key=component_key(component),
                     component_name=component.name,
+                    confidence_level=(
+                        EvidenceConfidence.PROVENANCE_RECORDED.value
+                        if component.provenance is not None
+                        else EvidenceConfidence.POLICY_MATCHED.value
+                    ),
                 ),
                 blocking_violations=blocking_violations,
                 warning_violations=warning_violations,
@@ -111,6 +124,7 @@ def evaluate_policy(
                     observed_value=False,
                     component_key=component_key(component),
                     component_name=component.name,
+                    confidence_level=EvidenceConfidence.PROVENANCE_RECORDED.value,
                 ),
                 blocking_violations=blocking_violations,
                 warning_violations=warning_violations,
@@ -131,6 +145,7 @@ def evaluate_policy(
                     observed_value=list(assessment.publisher_kinds),
                     component_key=component_key(component),
                     component_name=component.name,
+                    confidence_level=EvidenceConfidence.PROVENANCE_RECORDED.value,
                 ),
                 blocking_violations=blocking_violations,
                 warning_violations=warning_violations,
@@ -165,6 +180,11 @@ def evaluate_policy(
                         observed_value=_provenance_observed_value(assessment),
                         component_key=component_key(component),
                         component_name=component.name,
+                        confidence_level=(
+                            EvidenceConfidence.PROVENANCE_RECORDED.value
+                            if component.provenance is not None
+                            else EvidenceConfidence.POLICY_MATCHED.value
+                        ),
                     ),
                     blocking_violations=blocking_violations,
                     warning_violations=warning_violations,
@@ -243,6 +263,7 @@ def evaluate_policy(
                     observed_value=scorecard_score,
                     component_key=component_key(component),
                     component_name=component.name,
+                    confidence_level=EvidenceConfidence.SCORECARD_RECORDED.value,
                 ),
                 blocking_violations=blocking_violations,
                 warning_violations=warning_violations,
@@ -300,6 +321,7 @@ def _policy_violation(
     component_key: str | None = None,
     component_name: str | None = None,
     finding_bucket: str | None = None,
+    confidence_level: str = EvidenceConfidence.POLICY_MATCHED.value,
 ) -> PolicyViolation:
     return PolicyViolation(
         rule_id=rule_id,
@@ -313,6 +335,7 @@ def _policy_violation(
         component_key=component_key,
         component_name=component_name,
         finding_bucket=finding_bucket,
+        confidence_level=confidence_level,
     )
 
 
@@ -340,6 +363,7 @@ def _record_violation(
                 component_name=violation.component_name,
                 finding_bucket=violation.finding_bucket,
                 suppression_reason="ignored_by_policy",
+                confidence_level=violation.confidence_level,
             )
         )
         return 1
@@ -359,6 +383,7 @@ def _record_violation(
             component_key=violation.component_key,
             component_name=violation.component_name,
             finding_bucket=violation.finding_bucket,
+            confidence_level=violation.confidence_level,
         ),
         blocking_violations,
         warning_violations,
diff --git a/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_models.py b/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_models.py
index bc4a955..ababea0 100644
--- a/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_models.py
+++ b/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_models.py
@@ -4,6 +4,8 @@
 from enum import StrEnum
 from typing import Any
 
+from .schema_versions import POLICY_SCHEMA_V1
+
 
 class PolicyLevel(StrEnum):
     BLOCK = "block"
@@ -42,6 +44,7 @@ class PolicyLevel(StrEnum):
 @dataclass(slots=True, frozen=True)
 class PolicyConfig:
     version: int
+    policy_schema: str = POLICY_SCHEMA_V1
     block_on: tuple[str, ...] = ()
     warn_on: tuple[str, ...] = ()
     max_added_packages: int | None = None
@@ -68,6 +71,7 @@ class PolicyViolation:
     component_name: str | None = None
     finding_bucket: str | None = None
     suppression_reason: str | None = None
+    confidence_level: str = "policy_matched"
 
 
 @dataclass(slots=True)
diff --git a/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_parser.py b/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_parser.py
index ff3751f..023f03d 100644
--- a/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_parser.py
+++ b/tools/sbom-diff-and-risk/src/sbom_diff_risk/policy_parser.py
@@ -14,8 +14,10 @@
     V2_PROVENANCE_POLICY_RULE_IDS,
     V3_SCORECARD_POLICY_RULE_IDS,
 )
+from .schema_versions import POLICY_SCHEMA_V1
 
 _V1_SUPPORTED_POLICY_KEYS = {
+    "policy_schema",
     "version",
     "block_on",
     "warn_on",
@@ -55,6 +57,15 @@ def load_policy(path: Path) -> PolicyConfig:
     if unknown_keys:
         raise PolicyError(f"Invalid policy schema in {path}: unsupported keys: {', '.join(unknown_keys)}.")
 
+    policy_schema = payload.get("policy_schema", POLICY_SCHEMA_V1)
+    if not isinstance(policy_schema, str):
+        raise PolicyError(f"Invalid policy schema in {path}: policy_schema must be a string.")
+    if policy_schema != POLICY_SCHEMA_V1:
+        raise PolicyError(
+            f"Invalid policy schema in {path}: unsupported policy_schema {policy_schema!r}; "
+            f"expected {POLICY_SCHEMA_V1!r}."
+        )
+
     version = payload.get("version")
     if not isinstance(version, int):
         raise PolicyError(f"Invalid policy schema in {path}: version must be an integer.")
@@ -132,6 +143,7 @@ def load_policy(path: Path) -> PolicyConfig:
     return normalize_policy(
         PolicyConfig(
             version=version,
+            policy_schema=policy_schema,
             block_on=block_on,
             warn_on=warn_on,
             max_added_packages=max_added_packages,
@@ -166,6 +178,7 @@ def build_policy(
     seed = base_policy or PolicyConfig(version=1)
     merged = PolicyConfig(
         version=seed.version,
+        policy_schema=seed.policy_schema,
         block_on=_merge_strings(seed.block_on, cli_block_on),
         warn_on=_merge_strings(seed.warn_on, cli_warn_on),
         max_added_packages=seed.max_added_packages,
@@ -187,6 +200,7 @@ def normalize_policy(policy: PolicyConfig) -> PolicyConfig:
     ignore_rules = tuple(dict.fromkeys(policy.ignore_rules))
     return PolicyConfig(
         version=normalized_version,
+        policy_schema=policy.policy_schema,
         block_on=block_on,
         warn_on=warn_on,
         max_added_packages=policy.max_added_packages,
diff --git a/tools/sbom-diff-and-risk/src/sbom_diff_risk/presentation.py b/tools/sbom-diff-and-risk/src/sbom_diff_risk/presentation.py
index 7200391..dba261b 100644
--- a/tools/sbom-diff-and-risk/src/sbom_diff_risk/presentation.py
+++ b/tools/sbom-diff-and-risk/src/sbom_diff_risk/presentation.py
@@ -148,6 +148,7 @@ def policy_config_to_dict(policy: PolicyConfig | None) -> dict[str, Any] | None:
     if policy is None:
         return None
     payload = {
+        "policy_schema": policy.policy_schema,
         "version": policy.version,
         "block_on": list(policy.block_on),
         "warn_on": list(policy.warn_on),
@@ -176,9 +177,17 @@ def policy_config_to_dict(policy: PolicyConfig | None) -> dict[str, Any] | None:
 def policy_violation_to_dict(violation: PolicyViolation) -> dict[str, Any]:
     return {
         "rule_id": violation.rule_id,
+        "matched_rule_id": violation.policy_rule or violation.rule_id,
         "level": violation.level.value if violation.level is not None else None,
         "message": violation.message,
         "decision_reason": violation.decision_reason,
+        "exact_evidence": {
+            "component_key": violation.component_key,
+            "finding_bucket": violation.finding_bucket,
+            "matched_threshold": violation.matched_threshold,
+            "observed_value": violation.observed_value,
+        },
+        "confidence_level": violation.confidence_level,
         "policy_rule": violation.policy_rule,
         "severity_source": violation.severity_source,
         "matched_threshold": violation.matched_threshold,
diff --git a/tools/sbom-diff-and-risk/src/sbom_diff_risk/report_json.py b/tools/sbom-diff-and-risk/src/sbom_diff_risk/report_json.py
index 3f8994b..cbc8961 100644
--- a/tools/sbom-diff-and-risk/src/sbom_diff_risk/report_json.py
+++ b/tools/sbom-diff-and-risk/src/sbom_diff_risk/report_json.py
@@ -8,6 +8,7 @@
 from .presentation import build_policy_report_sections, build_trust_signal_report_sections
 from .policy_models import PolicyEvaluation
 from .scorecard_enrichment import scorecard_evidence_to_dict
+from .schema_versions import POLICY_SCHEMA_V1, REPORT_SCHEMA_V1
 
 
 def render_report_json(report: CompareReport) -> str:
@@ -15,6 +16,7 @@ def render_report_json(report: CompareReport) -> str:
     trust_signal_sections = build_trust_signal_report_sections(report)
     evidence_confidence = evidence_confidence_value(report)
     payload = {
+        "report_schema": REPORT_SCHEMA_V1,
         "summary": _summary_to_dict(report),
         "evidence_confidence": evidence_confidence,
         "components": {
@@ -57,7 +59,9 @@ def render_summary_json(report: CompareReport) -> str:
 
 def render_policy_json(report: CompareReport) -> str:
     policy_sections = build_policy_report_sections(report.metadata.policy_evaluation)
+    effective_policy = report.metadata.policy_evaluation.effective_policy if report.metadata.policy_evaluation else None
     payload: dict[str, object] = {
+        "policy_schema": effective_policy.policy_schema if effective_policy is not None else POLICY_SCHEMA_V1,
         "policy_evaluation": policy_sections["policy_evaluation"],
         "blocking_findings": policy_sections["blocking_findings"],
         "warning_findings": policy_sections["warning_findings"],
diff --git a/tools/sbom-diff-and-risk/src/sbom_diff_risk/schema_versions.py b/tools/sbom-diff-and-risk/src/sbom_diff_risk/schema_versions.py
new file mode 100644
index 0000000..2c5c100
--- /dev/null
+++ b/tools/sbom-diff-and-risk/src/sbom_diff_risk/schema_versions.py
@@ -0,0 +1,5 @@
+from __future__ import annotations
+
+
+POLICY_SCHEMA_V1 = "sbom-diff-risk.policy.v1"
+REPORT_SCHEMA_V1 = "sbom-diff-risk.report.v1"
diff --git a/tools/sbom-diff-and-risk/tests/test_cli_policy_json.py b/tools/sbom-diff-and-risk/tests/test_cli_policy_json.py
index 1472e5b..96c3a31 100644
--- a/tools/sbom-diff-and-risk/tests/test_cli_policy_json.py
+++ b/tools/sbom-diff-and-risk/tests/test_cli_policy_json.py
@@ -4,6 +4,7 @@
 from pathlib import Path
 
 from sbom_diff_risk import cli
+from sbom_diff_risk.schema_versions import POLICY_SCHEMA_V1
 
 
 def test_cli_policy_json_writes_policy_only_file(tmp_path: Path) -> None:
@@ -27,6 +28,7 @@ def test_cli_policy_json_writes_policy_only_file(tmp_path: Path) -> None:
     payload = json.loads(policy_path.read_text(encoding="utf-8"))
 
     assert exit_code == 1
+    assert payload["policy_schema"] == POLICY_SCHEMA_V1
     assert payload["summary"]["policy"] == {
         "status": "fail",
         "blocking": 3,
@@ -91,6 +93,7 @@ def test_cli_policy_json_without_policy_records_not_applied(tmp_path: Path) -> N
     payload = json.loads(policy_path.read_text(encoding="utf-8"))
 
     assert exit_code == 0
+    assert payload["policy_schema"] == POLICY_SCHEMA_V1
     assert payload["policy_evaluation"]["applied"] is False
     assert payload["policy_evaluation"]["exit_code"] == 0
     assert "summary" not in payload
@@ -122,7 +125,12 @@ def test_cli_policy_json_omitted_does_not_write_policy_file(tmp_path: Path) -> N
 
 
 def _policy_sidecar_from_full_report(report_payload: dict[str, object]) -> dict[str, object]:
+    evaluation = report_payload["policy_evaluation"]
+    assert isinstance(evaluation, dict)
+    effective_policy = evaluation["effective_policy"]
+    assert isinstance(effective_policy, dict)
     policy_payload = {
+        "policy_schema": effective_policy["policy_schema"],
         "policy_evaluation": report_payload["policy_evaluation"],
         "blocking_findings": report_payload["blocking_findings"],
         "warning_findings": report_payload["warning_findings"],
diff --git a/tools/sbom-diff-and-risk/tests/test_policy.py b/tools/sbom-diff-and-risk/tests/test_policy.py
index 5aa933f..0bb008e 100644
--- a/tools/sbom-diff-and-risk/tests/test_policy.py
+++ b/tools/sbom-diff-and-risk/tests/test_policy.py
@@ -9,6 +9,7 @@
 from sbom_diff_risk.policy_evaluator import evaluate_policy
 from sbom_diff_risk.policy_models import PolicyConfig, PolicyLevel
 from sbom_diff_risk.policy_parser import build_policy, load_policy
+from sbom_diff_risk.schema_versions import POLICY_SCHEMA_V1
 
 
 def test_policy_parser_accepts_minimal_policy() -> None:
@@ -16,6 +17,7 @@ def test_policy_parser_accepts_minimal_policy() -> None:
 
     policy = load_policy(policy_path)
 
+    assert policy.policy_schema == POLICY_SCHEMA_V1
     assert policy.version == 1
     assert policy.block_on == ("unknown_license",)
     assert policy.warn_on == ("new_package",)
@@ -37,6 +39,28 @@ def test_policy_parser_rejects_unknown_key(tmp_path: Path) -> None:
         load_policy(path)
 
 
+def test_policy_parser_accepts_legacy_policy_without_schema_identifier(tmp_path: Path) -> None:
+    path = tmp_path / "policy.yml"
+    path.write_text("version: 1\nwarn_on: [new_package]\n", encoding="utf-8")
+
+    policy = load_policy(path)
+
+    assert policy.policy_schema == POLICY_SCHEMA_V1
+
+
+@pytest.mark.parametrize("schema", ["sbom-diff-risk.policy.v2", 1])
+def test_policy_parser_rejects_unsupported_policy_schema(tmp_path: Path, schema: object) -> None:
+    path = tmp_path / "policy.yml"
+    if isinstance(schema, str):
+        rendered_schema = schema
+    else:
+        rendered_schema = str(schema)
+    path.write_text(f"policy_schema: {rendered_schema}\nversion: 1\n", encoding="utf-8")
+
+    with pytest.raises(PolicyError, match="policy_schema"):
+        load_policy(path)
+
+
 def test_policy_parser_rejects_invalid_version(tmp_path: Path) -> None:
     path = tmp_path / "policy.yml"
     path.write_text("version: 4\n", encoding="utf-8")
@@ -87,6 +111,7 @@ def test_policy_evaluator_blocks_on_finding_bucket() -> None:
     assert evaluation.blocking_violations[0].severity_source == "block_on"
     assert evaluation.blocking_violations[0].matched_threshold is None
     assert evaluation.blocking_violations[0].observed_value == "unknown_license"
+    assert evaluation.blocking_violations[0].confidence_level == "policy_matched"
 
 
 def test_policy_evaluator_warns_on_rule_when_configured() -> None:
diff --git a/tools/sbom-diff-and-risk/tests/test_policy_decision_examples.py b/tools/sbom-diff-and-risk/tests/test_policy_decision_examples.py
index 4e445f5..d981572 100644
--- a/tools/sbom-diff-and-risk/tests/test_policy_decision_examples.py
+++ b/tools/sbom-diff-and-risk/tests/test_policy_decision_examples.py
@@ -3,6 +3,8 @@
 import json
 from pathlib import Path
 
+from sbom_diff_risk.schema_versions import POLICY_SCHEMA_V1
+
 
 EXAMPLES_DIR = Path(__file__).resolve().parents[1] / "examples" / "policy-decisions"
 DECISION_FILES = {
@@ -62,6 +64,18 @@ def test_pass_warn_fail_examples_mirror_runtime_policy_statuses() -> None:
             assert policy_summary["blocking"] > 0
             assert any(finding["level"] == "block" for finding in payload["policy_findings"])
 
+        assert payload["policy_schema"] == POLICY_SCHEMA_V1
+        for finding in payload["policy_findings"]:
+            assert finding["matched_rule_id"] == finding["rule_id"]
+            assert set(finding["exact_evidence"]) == {
+                "component_key",
+                "finding_bucket",
+                "matched_threshold",
+                "observed_value",
+            }
+            assert finding["decision_reason"]
+            assert finding["confidence_level"] == "policy_matched"
+
 
 def test_needs_review_is_consumer_interpretation_not_runtime_status() -> None:
     payload = _read_example("needs-review.json")
diff --git a/tools/sbom-diff-and-risk/tests/test_report_schema_compatibility.py b/tools/sbom-diff-and-risk/tests/test_report_schema_compatibility.py
new file mode 100644
index 0000000..c6c5b5f
--- /dev/null
+++ b/tools/sbom-diff-and-risk/tests/test_report_schema_compatibility.py
@@ -0,0 +1,86 @@
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+
+from sbom_diff_risk.schema_versions import POLICY_SCHEMA_V1, REPORT_SCHEMA_V1
+
+
+_FULL_REPORT_FIXTURES = (
+    "sample-report.json",
+    "sample-policy-warn-report.json",
+    "sample-policy-fail-report.json",
+    "sample-requirements-report.json",
+    "sample-provenance-report.json",
+    "sample-scorecard-report.json",
+)
+
+_REQUIRED_REPORT_FIELDS = {
+    "report_schema",
+    "summary",
+    "evidence_confidence",
+    "components",
+    "risks",
+    "policy_evaluation",
+    "blocking_findings",
+    "warning_findings",
+    "suppressed_findings",
+    "rule_catalog",
+    "metadata",
+    "notes",
+}
+
+_REQUIRED_POLICY_DECISION_FIELDS = {
+    "rule_id",
+    "matched_rule_id",
+    "decision_reason",
+    "exact_evidence",
+    "confidence_level",
+}
+
+
+@pytest.mark.parametrize("fixture_name", _FULL_REPORT_FIXTURES)
+def test_full_report_fixtures_are_v1_compatible(fixture_name: str) -> None:
+    payload = _read_json_fixture(fixture_name)
+
+    assert payload["report_schema"] == REPORT_SCHEMA_V1
+    assert set(payload) >= _REQUIRED_REPORT_FIELDS
+    assert isinstance(payload["summary"], dict)
+    assert isinstance(payload["components"], dict)
+    assert isinstance(payload["risks"], list)
+    assert isinstance(payload["metadata"], dict)
+    assert isinstance(payload["notes"], list)
+
+    for section in ("blocking_findings", "warning_findings", "suppressed_findings"):
+        findings = payload[section]
+        assert isinstance(findings, list)
+        for finding in findings:
+            assert set(finding) >= _REQUIRED_POLICY_DECISION_FIELDS
+            assert finding["matched_rule_id"] == finding["rule_id"]
+            assert set(finding["exact_evidence"]) == {
+                "component_key",
+                "finding_bucket",
+                "matched_threshold",
+                "observed_value",
+            }
+            assert finding["confidence_level"] in {
+                "policy_matched",
+                "provenance_recorded",
+                "scorecard_recorded",
+            }
+
+
+def test_policy_sidecar_uses_v1_policy_schema() -> None:
+    payload = _read_json_fixture("sample-policy.json")
+
+    assert payload["policy_schema"] == POLICY_SCHEMA_V1
+    assert payload["policy_evaluation"]["effective_policy"]["policy_schema"] == POLICY_SCHEMA_V1
+
+
+def _read_json_fixture(name: str) -> dict[str, object]:
+    path = Path(__file__).resolve().parents[1] / "examples" / name
+    payload = json.loads(path.read_text(encoding="utf-8"))
+    assert isinstance(payload, dict)
+    return payload
diff --git a/tools/sbom-diff-and-risk/tests/test_reports.py b/tools/sbom-diff-and-risk/tests/test_reports.py
index f35ca14..757e5da 100644
--- a/tools/sbom-diff-and-risk/tests/test_reports.py
+++ b/tools/sbom-diff-and-risk/tests/test_reports.py
@@ -22,6 +22,7 @@
 from sbom_diff_risk.report_json import render_policy_json, render_report_json, render_summary_json
 from sbom_diff_risk.report_md import render_report_markdown
 from sbom_diff_risk.risk import evaluate_risks, summarize_risks
+from sbom_diff_risk.schema_versions import POLICY_SCHEMA_V1, REPORT_SCHEMA_V1
 
 
 def test_report_json_matches_cyclonedx_golden_pass() -> None:
@@ -124,6 +125,7 @@ def test_report_json_keeps_legacy_sections() -> None:
     payload = json.loads(render_report_json(report))
 
     assert set(payload) >= {
+        "report_schema",
         "summary",
         "evidence_confidence",
         "components",
@@ -141,6 +143,7 @@ def test_report_json_keeps_legacy_sections() -> None:
         "metadata",
         "notes",
     }
+    assert payload["report_schema"] == REPORT_SCHEMA_V1
     assert payload["metadata"]["policy_evaluation"] == payload["policy_evaluation"]
     assert payload["metadata"]["enrichment"] == payload["enrichment_metadata"]
     assert payload["metadata"]["evidence_confidence"] == payload["evidence_confidence"]
@@ -222,7 +225,15 @@ def test_report_json_policy_findings_include_explanation_fields() -> None:
     finding = payload["warning_findings"][0]
 
     assert finding["rule_id"] == "new_package"
+    assert finding["matched_rule_id"] == "new_package"
     assert finding["decision_reason"] == "risk_finding_matched_policy_rule"
+    assert finding["exact_evidence"] == {
+        "component_key": finding["component_key"],
+        "finding_bucket": "new_package",
+        "matched_threshold": None,
+        "observed_value": "new_package",
+    }
+    assert finding["confidence_level"] == "policy_matched"
     assert finding["policy_rule"] == "new_package"
     assert finding["severity_source"] == "warn_on"
     assert finding["matched_threshold"] is None
@@ -419,7 +430,12 @@ def _read_example(name: str) -> str:
 
 
 def _policy_sidecar_from_full_report(report_payload: dict[str, object]) -> dict[str, object]:
+    evaluation = report_payload["policy_evaluation"]
+    assert isinstance(evaluation, dict)
+    effective_policy = evaluation["effective_policy"]
+    assert isinstance(effective_policy, dict)
     policy_payload = {
+        "policy_schema": effective_policy["policy_schema"],
         "policy_evaluation": report_payload["policy_evaluation"],
         "blocking_findings": report_payload["blocking_findings"],
         "warning_findings": report_payload["warning_findings"],