ln-614-docs-fact-checker

Paths: File paths (references/, ../ln-*) are relative to this skill directory.

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 references/audit_worker_core_contract.md, references/docs_quality_contract.md, and references/markdown_read_protocol.md. Optional rule catalog: load references/docs_quality_rules.json only when exact rule IDs, path matrices, or allowlisted placeholder exceptions are needed. Tool policy: follow host AGENTS.md MCP preferences; load references/mcp_tool_preferences.md and references/mcp_integration_patterns.md only when host policy is absent or MCP behavior is unclear.

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)

Detection policy: use two-layer detection (candidate scan, then context verification); load references/two_layer_detection.md only when the verification method is ambiguous.

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](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|formats|endpoints|services|tables|parsers|files|workers) | | 4 | API endpoints | HTTP method + path | (GET|POST|PUT|DELETE|PATCH) /[\w/{}:]+ | | 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 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