Ln 014 Agent Instructions Manager

⚠️ External ecosystem dependency: This skill is designed for the ln-* skills ecosystem and relies on paths (shared/references/, skills-catalog/ln-111-root-docs-creator/, etc.) that do not exist in this repo (copilot-session-knowledge). Phases that require those paths (template creation, MCP Tool Preferences insertion, plugin conflict checks) will fail when run standalone here. The audit-only phases (token budget, cache safety, import-pattern compliance) remain usable without the external ecosystem.

For instruction-file creation in this repo, see root AGENTS.md.

Paths: All file refs relative to skills repo root.

Agent Instructions Manager

Type: L3 Worker Category: 0XX Shared

Creates missing instruction files and audits all of them (AGENTS.md, CLAUDE.md, GEMINI.md, ANTIGRAVITY.md) for quality, consistency, and best practices. AGENTS.md is the single canonical source of content; CLAUDE.md, GEMINI.md, and ANTIGRAVITY.md are thin @AGENTS.md import stubs with bounded harness-specific deltas. This skill is the single owner of instruction-file creation and MCP Tool Preferences insertion or replacement.

MANDATORY READ: Load shared/references/coordinator_summary_contract.md, shared/references/environment_worker_runtime_contract.md, and shared/references/worker_runtime_contract.md MANDATORY READ: Load shared/references/mcp_tool_preferences.md MANDATORY READ: Load shared/references/agent_instructions_writing_guide.md — canonical rationale for the @AGENTS.md import pattern, size budgets, and anti-patterns. All audit checks below trace back to this guide.

Input / Output

If summaryArtifactPath is provided, write the same summary JSON there. If not provided, return the summary inline and remain fully standalone. If runId is not provided, generate a standalone run_id before emitting the summary envelope.

Runtime

Runtime family: environment-worker-runtime

Phase profile:

1. PHASE_0_CONFIG
2. PHASE_1_DISCOVER_FILES
3. PHASE_2_CREATE_MISSING_FILES
4. PHASE_3_TOKEN_BUDGET_AUDIT
5. PHASE_4_PROMPT_CACHE_SAFETY
6. PHASE_5_CONTENT_QUALITY
7. PHASE_6_IMPORT_PATTERN_COMPLIANCE
8. PHASE_7_WRITE_SUMMARY
9. PHASE_8_SELF_CHECK

Runtime rules:

• emit summary_kind=env-instructions
• standalone runs generate their own run_id and write the default worker-family artifact path
• managed runs require both runId and summaryArtifactPath and must write the summary to the exact provided path
• always write the validated summary artifact before terminal outcome

Output Contract

Always build a structured env-instructions summary envelope per:

• shared/references/coordinator_summary_contract.md
• shared/references/environment_worker_runtime_contract.md

Payload fields:

• files_found
• files_created
• quality_findings
• token_budget
• prompt_cache_safety
• import_pattern_status
• status

When to Use

• After editing any instruction file
• After adding/removing MCP servers or hooks
• Before release or publishing
• When sessions degrade (context bloat symptoms)
• First-time project setup (instruction files missing)

Phase 1: Discover Files

Locate instruction files in target project:

Report: which files exist (found / missing), which harnesses share AGENTS.md directly vs via import.

Phase 1b: Plugin Conflict Check

Skip condition: No enabledPlugins in settings OR all plugins are @levnikolaevich-skills-marketplace.

1. Read ~/.claude/settings.json → parse enabledPlugins
2. Filter: enabled=true AND publisher ≠ levnikolaevich-skills-marketplace
3. For each external plugin:
   • Resolve active install first: matching plugin or marketplace under ~/.claude/plugins/marketplaces/*
   • Read active skills-catalog/*/SKILL.md descriptions from that install surface
   • Only if no active install is available, fall back to the latest cache snapshot under ~/.claude/plugins/cache/{publisher}/{plugin}/*/skills/*/SKILL.md
   • Treat cache as forensic fallback only. Never count multiple cache snapshots as separate active conflicts.
   • Match against conflict signal keywords:

• Check for hooks/session-start directory in the active install surface first

4. Score: 2+ signal categories → CONFLICT. 1 → WARN. 0 → safe
5. CONFLICT: "CONFLICT: {plugin} overlaps with ln-* pipeline ({signals}). Disable?" → AskUserQuestion → if yes, set to false in settings.json
6. WARN: report, continue

Phase 2: Create Missing Files

Skip condition: All files exist OR dry_run == true (report what would be created).

Canonical model: AGENTS.md is the single source of content. CLAUDE.md, GEMINI.md, and ANTIGRAVITY.md are @AGENTS.md import stubs with bounded harness-specific deltas. Create in this order so the stubs reference a file that already exists.

Step 2a: Detect Project Context

Step 2b: Create AGENTS.md (if missing) — canonical

1. MANDATORY READ: Load skills-catalog/ln-111-root-docs-creator/references/templates/agents_md_template.md
2. Replace {{PROJECT_NAME}}, {{PROJECT_DESCRIPTION}}, {{DATE}}, and {{DEV_COMMANDS_*}} placeholders
3. If ENABLE_WORKFLOW_PRINCIPLES=true: replace {{WORKFLOW_PRINCIPLES_BLOCK}} with the full content of skills-catalog/ln-111-root-docs-creator/references/templates/agents_md_workflow_principles.md. Otherwise strip the placeholder line and its leading HTML comment.
4. Mark remaining {{...}} as [TBD: placeholder_name]
5. Write to target project root

Step 2c: Create CLAUDE.md (if missing) — import stub

1. MANDATORY READ: Load skills-catalog/ln-111-root-docs-creator/references/templates/claude_md_template.md
2. Replace {{PROJECT_NAME}} only
3. Write to target project root
4. Verify the file contains exactly one @AGENTS.md line and is ≤50 lines total
5. Do NOT copy any content from AGENTS.md into CLAUDE.md — the @ import handles it at session load time

Step 2d: Create GEMINI.md (if missing) — import stub

1. MANDATORY READ: Load skills-catalog/ln-111-root-docs-creator/references/templates/gemini_md_template.md
2. Replace {{PROJECT_NAME}} only
3. Write to target project root
4. Verify the file contains exactly one @AGENTS.md line and is ≤50 lines total
5. Do NOT copy any content from AGENTS.md into GEMINI.md — the @ import handles it at session load time

Step 2d2: Create ANTIGRAVITY.md (if missing) — import stub

1. MANDATORY READ: Load skills-catalog/ln-111-root-docs-creator/references/templates/antigravity_md_template.md
2. Replace {{PROJECT_NAME}} only
3. Write to target project root
4. Verify the file contains exactly one @AGENTS.md line and is ≤50 lines total
5. Do NOT copy any content from AGENTS.md into ANTIGRAVITY.md — the @ import handles it at session load time

Step 2e: Report Creations

List each created file with its source (template agents_md_template.md, template claude_md_template.md stub, template gemini_md_template.md stub, template antigravity_md_template.md stub).

Phase 3: Token Budget Audit

Line-count budgets align with the Anthropic official target (<200 lines per CLAUDE.md file) and the IFScale instruction-ceiling research. See shared/references/agent_instructions_writing_guide.md for the full rationale.

Imperative counter: lines matching ^\s*- inside rule sections, plus any line containing MUST\|NEVER\|ALWAYS\|DO NOT. Cite the IFScale benchmark (arxiv 2507.11538) in WARN / FAIL messages.

Report table per file with line count and imperative count (for AGENTS.md).

Phase 4: Prompt Cache Safety

Check each file for content that breaks prefix-based prompt caching:

Phase 5: Content Quality

Checks #1–#6 evaluate AGENTS.md only because CLAUDE.md / GEMINI.md / ANTIGRAVITY.md inherit that content via the @AGENTS.md import. Checks on the deltas themselves live in Phase 6.

Phase 5b: Auto-fix Fixable Issues

For each FAIL in Phase 5, attempt auto-fix before reporting:

Before any auto-fix insertion:

1. Verify insertion point exists (exact heading found at specific line)
2. If ambiguous (heading not found) — WARN and skip (report as manual fix needed)
3. After insertion — verify no duplicate ## Compact Instructions or ## MCP Tool Preferences sections exist in the file

Compact Instructions template (insert in AGENTS.md before ## Navigation or after last rules section):

## Compact Instructions

Preserve during /compact: [Critical Rules], [MCP Tool Preferences table],
[Navigation table], [language/communication rules], [hard boundaries (NEVER/ALWAYS)].
Drop examples and explanations first.

Because CLAUDE.md, GEMINI.md, and ANTIGRAVITY.md @AGENTS.md, the preservation list propagates to all of them. The harness-specific terminology (/compact vs context compression) lives in each stub's delta.

Phase 6: Import Pattern Compliance

AGENTS.md is the canonical source per DOC_ROLE metadata. CLAUDE.md, GEMINI.md, and ANTIGRAVITY.md must be thin @AGENTS.md import stubs with bounded harness-specific deltas.

Drift resolution rule: AGENTS.md is the canonical source. For each inconsistency:

• (a) If content is missing from AGENTS.md but present in CLAUDE.md / GEMINI.md → move it to AGENTS.md, then remove from the stub.
• (b) If CLAUDE.md / GEMINI.md duplicate AGENTS.md content → replace with a single @AGENTS.md import line.
• (c) If the stub delta exceeds 50 lines → split genuinely harness-specific content into .claude/rules/*.md (for Claude) or modular @imports (for Gemini); everything else moves to AGENTS.md.

Do not "suggest which file is source of truth" based on content volume — AGENTS.md is always the source.

If .hex-skills/environment_state.json reports agents.codex.discovery_violation=true, emit a WARN that Codex skill discovery is drifted and duplicate skill counts from stale cache must not be used as evidence during instruction audits until ln-013-config-syncer repairs the mapping.

If .hex-skills/environment_state.json reports agents.codex.permissions_default_ready=false, emit a WARN that Codex CLI startup permissions are drifted from the managed default and instruction audits must not assume full-access startup semantics until ln-013-config-syncer repairs ~/.codex/config.toml.

Phase 7: Report

Agent Instructions Manager:

Created:  (omit section if nothing created)
- AGENTS.md (from template, context from package.json)
- CLAUDE.md (import stub)
- GEMINI.md (import stub)

Audit:
| File       | Lines | Imperatives | Cache-safe | Quality | Import pattern | Issues |
|------------|-------|-------------|------------|---------|----------------|--------|
| AGENTS.md  | 118   | 47          | OK         | 7/7     | n/a            | OK |
| CLAUDE.md  | 13    | 0           | OK         | 7/7     | OK             | OK |
| GEMINI.md  | 12    | 0           | OK         | 7/7     | OK             | OK |

Import pattern: OK (or N drift issues listed)

Recommendations:
1. Run /init (ln-100) for full context-aware AGENTS.md with project-specific rules

Cross-agent note: Codex CLI 0.120 (2026-04-11) now supports SessionStart hook with /clear vs fresh/resume distinction, matching Claude Code behavior.

Definition of Done

• All instruction files discovered
• Missing files created (AGENTS.md from template first; CLAUDE.md and GEMINI.md as @AGENTS.md import stubs second)
• Token budget within limits: AGENTS.md ≤200 lines, CLAUDE.md and GEMINI.md each ≤50 lines, AGENTS.md imperative count ≤150
• No prompt cache breakers found (or reported as WARN)
• Content quality checks passed on AGENTS.md (or issues reported)
• Auto-fixable issues resolved in AGENTS.md (Compact Instructions, MCP Tool Preferences) or reported if dry_run
• Import pattern compliance verified: CLAUDE.md and GEMINI.md each contain exactly one @AGENTS.md line and no duplicated AGENTS.md content
• Report generated with creation log, drift findings, and actionable recommendations
• No conflicting external plugins detected (or user confirmed keep)
• Structured summary returned
• Summary artifact written to the managed or standalone runtime path

Critical Rule: Non-destructive file edits. Auto-fix inserts sections at verified positions only. Never rewrite the entire instruction file. Preserve all existing content outside the inserted section.

Version: 2.2.0 Last Updated: 2026-03-25

1. Run the skill to create all instruction files from templates:

   • AGENTS.md created from template (118 lines, 47 imperatives)
   • CLAUDE.md created as @AGENTS.md import stub (13 lines)
   • GEMINI.md created as @AGENTS.md import stub (12 lines)

2. The skill reports its audit immediately after creation:

   File	Lines	Cache-safe	Quality	Import pattern	Issues
   AGENTS.md	118	OK	7/7	n/a	OK
   CLAUDE.md	13	OK	7/7	OK	OK
   GEMINI.md	12	OK	7/7	OK	OK

3. No conflicts detected with installed plugins.

1. Skill discovers: AGENTS.md (canonical), CLAUDE.md (stub), GEMINI.md (stub)
2. Phase 6 detects: CLAUDE.md has 3 sections duplicated from AGENTS.md + file is 72 lines
3. Fix applied: duplicated sections removed from CLAUDE.md, @AGENTS.md import preserved
4. Result: CLAUDE.md trimmed to 18 lines, all content now flowing through @AGENTS.md

Source: magicpro97/copilot-session-knowledge — distributed by TomeVault.