| name | ln-614-docs-fact-checker |
| description | Verifies claims in .md files (paths, versions, counts, configs, endpoints) against codebase, cross-checks contradictions. Use when auditing docs accuracy. |
| allowed-tools | Read, Grep, Glob, Bash, mcp__hex-line__outline, mcp__hex-line__read_file, mcp__hex-graph__index_project, mcp__hex-graph__find_symbols, mcp__hex-graph__find_references |
| license | MIT |
Paths: File paths (shared/, references/, ../ln-*) are relative to skills repo root. If not found at CWD, locate this SKILL.md directory and go up one level for repo root. If shared/ is missing, fetch files via WebFetch from https://raw.githubusercontent.com/levnikolaevich/claude-code-skills/master/skills/{path}.
Documentation Fact-Checker (L3 Worker)
Type: L3 Worker
Specialized worker that extracts verifiable claims from documentation and validates each against the actual codebase.
Purpose & Scope
- Prioritize canonical and high-claim docs, then extract verifiable claims from markdown documentation
- Verify each claim against codebase (Grep/Glob/Read/Bash)
- Detect cross-document contradictions (same fact stated differently)
- Includes
docs/reference/, docs/tasks/, tests/ in scope
- Single invocation (not per-document) -> cross-doc checks require global view
- Does NOT check scope alignment or structural quality
Inputs
MANDATORY READ: Load shared/references/audit_worker_core_contract.md, shared/references/docs_quality_contract.md, shared/references/docs_quality_rules.json, shared/references/markdown_read_protocol.md, shared/references/mcp_tool_preferences.md, and shared/references/mcp_integration_patterns.md.
Receives contextStore with: tech_stack, project_root, output_dir.
Workflow
Phase 1: Parse Context
Extract tech stack, project root, output_dir from contextStore.
Phase 2: Discover Documents
Glob markdown docs in project. Exclude:
node_modules/, .git/, dist/, build/docs/project/.audit/ (audit output, not project docs)CHANGELOG.md (historical by design)
If docs/project/.context/doc_registry.json exists:
- load it first
- prioritize
doc_role=canonical
- prioritize files with dense claim types (paths, endpoints, versions, commands)
- de-prioritize navigation hubs unless contradictions point back to them
Phase 3: Extract Claims (Layer 1)
MANDATORY READ: Load shared/references/two_layer_detection.md for detection methodology.
For each prioritized document, use section-first reads to extract verifiable claims using Grep/regex patterns.
For code files referenced by docs, use outline() and discovery-first read_file() before built-in reads. Only request edit_ready=true, verbosity="full" if verification turns into a follow-up edit. Use hex-graph only when entity identity or reference resolution remains ambiguous after direct manifest/file checks.
MANDATORY READ: Load references/claim_extraction_rules.md for detailed extraction patterns per claim type.
9 claim types:
| # | Claim Type | What to Extract | Extraction Pattern |
|---|
| 1 | File paths | Paths to source files, dirs, configs | Backtick paths, link targets matching src/, lib/, app/, docs/, config/, tests/ |
| 2 | Versions | Package/tool/image versions | Semver patterns near dependency/package/image names |
| 3 | Counts/Statistics | Numeric claims about codebase | `\d+ (modules |
| 4 | API endpoints | HTTP method + path | `(GET |
| 5 | Config keys/env vars | Environment variables, config keys | [A-Z][A-Z_]{2,} in config context, process.env., os.environ |
| 6 | CLI commands | Shell commands | npm run, python, docker, make in backtick blocks |
| 7 | Function/class names | Code entity references | CamelCase/snake_case in backticks or code context |
| 8 | Line number refs | file:line patterns | [\w/.]+:\d+ patterns |
| 9 | Docker/infra claims | Image tags, ports, service names | Image names with tags, port mappings in docker context |
Output per claim: {doc_path, line, claim_type, claim_value, raw_context}.
Phase 4: Verify Claims (Layer 2)
For each extracted claim, verify against codebase:
| Claim Type | Verification Method | Finding Type |
|---|
| File paths | Glob or ls for existence | PATH_NOT_FOUND |
| Versions | Grep package files (package.json, requirements.txt, docker-compose.yml), compare | VERSION_MISMATCH |
| Counts | Glob/Grep to count actual entities, compare with claimed number | COUNT_MISMATCH |
| API endpoints | Grep route/controller definitions | ENDPOINT_NOT_FOUND |
| Config keys | Grep in source for actual usage | CONFIG_NOT_FOUND |
| CLI commands | Check package.json scripts, Makefile targets, binary existence | COMMAND_NOT_FOUND |
| Function/class | Grep in source for definition | ENTITY_NOT_FOUND |
| Line numbers | Read file at line, check content matches claimed context | LINE_MISMATCH |
| Docker/infra | Grep docker-compose.yml for image tags, ports | INFRA_MISMATCH |
False positive filtering (Layer 2 reasoning):
- Template placeholders (
{placeholder}, YOUR_*, <project>, xxx) -> skip
- Example/hypothetical paths (preceded by "e.g.", "for example", "such as") -> skip
- Future-tense claims ("will add", "planned", "TODO") -> skip or LOW
- Conditional claims ("if using X, configure Y") -> verify only if X detected in tech_stack
- External service paths (URLs, external repos) -> skip
- Paths in SCOPE/comment HTML blocks describing other projects -> skip
.env.example values -> skip (expected to differ from actual)
Phase 5: Cross-Document Consistency
Compare extracted claims across documents to find contradictions:
| Check | Method | Finding Type |
|---|
| Same path, different locations | Group file path claims, check if all point to same real path | CROSS_DOC_PATH_CONFLICT |
| Same entity, different version | Group version claims by entity name, compare values | CROSS_DOC_VERSION_CONFLICT |
| Same metric, different count | Group count claims by subject, compare values | CROSS_DOC_COUNT_CONFLICT |
| Endpoint in spec but not in guide | Compare endpoint claims across api_spec.md vs guides/runbook | CROSS_DOC_ENDPOINT_GAP |
Algorithm:
claim_index = {} # key: normalized(claim_type + entity), value: [{doc, line, value}]
FOR claim IN all_verified_claims WHERE claim.verified == true:
key = normalize(claim.claim_type, claim.entity_name)
claim_index[key].append({doc: claim.doc_path, line: claim.line, value: claim.claim_value})
FOR key, entries IN claim_index:
unique_values = set(entry.value for entry in entries)
IF len(unique_values) > 1:
CREATE finding(type=CROSS_DOC_*_CONFLICT, severity=HIGH,
location=entries[0].doc + ":" + entries[0].line,
issue="'" + key + "' stated as '" + val1 + "' in " + doc1 + " but '" + val2 + "' in " + doc2)
Phase 6: Score & Report
MANDATORY READ: Load shared/references/audit_worker_core_contract.md and shared/references/audit_scoring.md.
Calculate score using penalty formula. Write report.
Audit Categories (for Checks table)
| ID | Check | What It Covers |
|---|
path_claims | File/Directory Paths | All path references verified against filesystem |
version_claims | Version Numbers | Package, tool, image versions against manifests |
count_claims | Counts & Statistics | Numeric assertions against actual counts |
endpoint_claims | API Endpoints | Route definitions against controllers/routers |
config_claims | Config & Env Vars | Environment variables, config keys against source |
command_claims | CLI Commands | Scripts, commands against package.json/Makefile |
entity_claims | Code Entity Names | Functions, classes against source definitions |
line_ref_claims | Line Number References | file:line against actual file content |
cross_doc | Cross-Document Consistency | Same facts across documents agree |
Severity Mapping
| Issue Type | Severity | Rationale |
|---|
| PATH_NOT_FOUND (critical file: AGENTS.md, CLAUDE.md, runbook, api_spec) | CRITICAL | Setup/onboarding fails |
| PATH_NOT_FOUND (other docs) | HIGH | Misleading reference |
| VERSION_MISMATCH (major version) | HIGH | Fundamentally wrong |
| VERSION_MISMATCH (minor/patch) | MEDIUM | Cosmetic drift |
| COUNT_MISMATCH | MEDIUM | Misleading metric |
| ENDPOINT_NOT_FOUND | HIGH | API consumers affected |
| CONFIG_NOT_FOUND | HIGH | Deployment breaks |
| COMMAND_NOT_FOUND | HIGH | Setup/CI breaks |
| ENTITY_NOT_FOUND | MEDIUM | Confusion |
| LINE_MISMATCH | LOW | Minor inaccuracy |
| INFRA_MISMATCH | HIGH | Docker/deployment affected |
| CROSS_DOC_*_CONFLICT | HIGH | Trust erosion, contradictory docs |
Output Format
MANDATORY READ: Load shared/references/audit_worker_core_contract.md and shared/templates/audit_worker_report_template.md.
Write JSON summary per shared/references/audit_summary_contract.md. In managed mode the caller passes both runId and summaryArtifactPath; in standalone mode the worker generates its own run-scoped artifact path per shared contract.
Write report to {output_dir}/ln-614--global.md with category: "Fact Accuracy" and checks: path_claims, version_claims, count_claims, endpoint_claims, config_claims, command_claims, entity_claims, line_ref_claims, cross_doc.
Return summary per shared/references/audit_summary_contract.md.
When summaryArtifactPath is absent, write the standalone runtime summary under .hex-skills/runtime-artifacts/runs/{run_id}/evaluation-worker/{worker}--{identifier}.json and optionally echo the same summary in structured output.
Report written: .hex-skills/runtime-artifacts/runs/{run_id}/audit-report/ln-614--global.md
Score: X.X/10 | Issues: N (C:N H:N M:N L:N)
Critical Rules
MANDATORY READ: Load shared/references/audit_worker_core_contract.md.
- Do not auto-fix: Report violations only; coordinator aggregates for user
- Code is truth: When docs contradict code, document is wrong (unless code is a bug)
- Evidence required: Every finding includes verification command used and result
- No false positives: Better to miss an issue than report incorrectly. When uncertain, classify as LOW with note
- Location precision: Always include
file:line for programmatic navigation
- Broad scope: Scan ALL .md files -- do not skip docs/reference/, tests/, or task docs
- Targeted depth: Spend the deepest verification effort on canonical and high-claim docs first
- Cross-doc matters: Contradictions between documents erode trust more than single-doc errors
- Batch efficiently: Extract all claims first, then verify in batches by type (all paths together, all versions together)
- Shared placeholder policy: Respect allowlisted setup placeholders from
docs_quality_rules.json; do not escalate them in task setup docs
- Use hex-graph only for semantic ambiguity: For code entities and references, prefer graph queries over repeated grep only when direct manifest/file checks leave symbol identity or reference resolution ambiguous
Definition of Done
MANDATORY READ: Load shared/references/audit_worker_core_contract.md.
Reference Files
- Audit output schema:
shared/references/audit_output_schema.md
- Detection methodology:
shared/references/two_layer_detection.md
- Claim extraction rules: references/claim_extraction_rules.md
Version: 1.0.0
Last Updated: 2026-03-06
