AGENTS.md
Open Markdown 'README for agents' at repo root; nested files in subprojects take precedence (closest wins). Holds build/test commands, conventions and PR rules. Stewarded by the Agentic AI Foundation (Linux Foundation); supported by Codex, Jules, Cursor, Copilot, Gemini CLI, Devin/Windsurf and others.
Active · Verified 2026-10-22 · fresh as of 2026-10-22 · 52 cited facts, 2 with a third-party source · 1 recorded change · Suggest a correction
At a glance
- Type
- Cross-tool open standard vendor fix
- Tier
- T1
- Section
- File-backed / editor paradigms
- Created
- 2025-05 (introduced with OpenAI Codex CLI research preview May 16 2025; donated to Linux Foundation AAIF Dec 2025) third-party fix
- Latest release
- not applicable — not OSS fix
- GitHub
- agentsmd/agents.md — ~25k stars repo fix
- Pricing
- not applicable — not commercial fix
- Funding
- not applicable — not commercial fix
- Freshness
- 2026-10-22 fix
- Layer
- agent-infra repo fix
- Licensing
- open-source repo fix
- Developer activity
- OpenRank 2.42 (12-mo avg 3.69) · 28 participants — 2026-09 third-party fix
Memory taxonomy
- storage
- file
- retrieval
- injection
- persistence
- cross-session
- update
- overwrite
- unit
- document
- governance
- user-controllable
- conflict
- manual
When to use
Optimised for: simplicity / git-versioned / human-readable
Anti-fit: not for non-coding / non-IDE use cases
Pros & cons
Pros
Cross-vendor convention — the closest thing to a universal agent memory file format; works across Claude Code, Cursor, and Codex CLI.
Cons
Adoption is informal (no spec authority); agent-by-agent interpretation differences mean behavior isn't fully portable.
Claims & capabilities
Donated to Linux Foundation's AAIF (Dec 2025). Adopted by 20,000+ repos. Read by Codex CLI, GitHub Copilot, Cursor, Claude Code, Factory.ai.
Technical surface
- API surface
- not applicable — file convention
- Backend storage
- file (AGENTS.md)
- Deployment
- not applicable — not a deployable product
- Embedding model
- not applicable — file convention
- Multi-tenancy
- not applicable — file
- MCP
- not applicable — file-as-memory paradigm (no API surface)
- A2A
- not applicable — file-as-memory paradigm
- OpenTelemetry
- not applicable — file-as-memory paradigm
Compare AGENTS.md with…
Alternatives to AGENTS.md → live options ranked by shared design, licence, hosting and MCP support
Similar systems
Other file-backed / editor paradigms in the catalog, ranked by inbound references.
- Cline .clinerules T2
Markdown rule files in a workspace .clinerules/ (or .cline/rules/) directory plus global rules in ~/Documents/Cline/Rules; workspace wins on conflict. Per-rule toggles, conditional rules via YAML 'paths' globs, and AGENTS.md / .cursorrules / .windsurfrules are also read.
- OpenClaw memory T3
Memory system of the viral OpenClaw personal agent: plain Markdown files (USER.md, MEMORY.md, daily memory/YYYY-MM-DD.md notes, DREAMS.md) with memory_search/memory_get tools, automatic pre-compaction flush and a 'dreaming' sweep that distils daily notes into long-term memory; pluggable engines (LanceDB, Honcho, wiki). spawned an ecosystem of memory plugins (memory-lancedb-pro, gbrain, MemClaw)
- Aider CONVENTIONS.md / .aider.conf.yml T2
CONVENTIONS.md (any name, loaded via --read or read: in config); .aider.conf.yml (home / git-root / cwd, last wins); .aiderignore (gitignore-syntax).
- Basic Memory T3
Local-first MCP memory where each memory is a Markdown note with observations and wikilink relations that form a traversable knowledge graph, indexed with SQLite (optional Postgres vectors), plus an optional hosted cloud. widely used MCP memory server with a paid cloud tier
- CLAUDE.md T1
CLAUDE.md files (managed, user, project, local scopes) concatenated into context at session start, with @imports and path-scoped .claude/rules/; complemented by Claude-written auto memory (MEMORY.md index). Project-root file re-injected after /compact.
- Cline Memory Bank T2
memory-bank/ directory of Markdown: projectBrief.md , productContext.md , activeContext.md , systemPatterns.md , techContext.md , progress.md . Loaded in full at start of every task. Compensates for context-window reset between sessions.
Sources (51 cited facts, 2 third-party)
Each fact links to the page it came from; the badge says who published it (how to read sources).
- What it is Cross-tool open standard vendor
- What it does & what's distinct Open Markdown 'README for agents' at repo root; nested files in subprojects take precede… vendor
- Claims / benefits Donated to Linux Foundation's AAIF (Dec 2025). Adopted by 20,000+ repos. Read by Codex C… vendor
- Modalities text vendor
- Created 2025-05 (introduced with OpenAI Codex CLI research preview May 16 2025; donated to Linux… third-party
- License MIT repo
- GitHub agentsmd/agents.md — ~25k stars repo
- Founders / pedigree Open standard (community-driven); no single founding org vendor
- Memory volume / scale no scale claim — hierarchical markdown files vendor
- Backend storage file (AGENTS.md) vendor
- Consistency strong vendor
- Versioning snapshots vendor
- Tombstoning hard-delete supported vendor
- Schema evolution free-form / no schema vendor
- Namespace primitives hierarchical vendor
- Contradiction handling always overwrite (last-write-wins) vendor
- Forgetting policy user-controlled forget vendor
- Import / export Markdown / plain text (the file itself is the export) vendor
- Validated verticals coding agents only - software engineering teams vendor
- Time to running <10min (drop a file in repo) vendor
- Anti-fit not for non-coding / non-IDE use cases vendor
- Optimised for simplicity / git-versioned / human-readable vendor
- Adjacent infrastructure requires the corresponding IDE / editor vendor
- Pros Cross-vendor convention — the closest thing to a universal agent memory file format; wor… vendor
- Cons Adoption is informal (no spec authority); agent-by-agent interpretation differences mean… vendor
- Project & sources agents.md GitHub Blog vendor
- obs-langsmith no vendor
- obs-opentelemetry no vendor
- obs-datadog no vendor
- obs-helicone no vendor
- obs-weave no vendor
- obs-langfuse no vendor
- obs-arize no vendor
- obs-custom File-format specification — observability is a host-app concern vendor
- cost-token-budget no vendor
- cost-prompt-caching no vendor
- cost-semantic-caching no vendor
- cost-batching no vendor
- cost-model-routing no vendor
- cost-streaming-only no vendor
- cost-observability-cost-attribution no vendor
- eval-langsmith-evals no vendor
- eval-braintrust no vendor
- eval-weights-and-biases-agent no vendor
- eval-helicone-evals no vendor
- eval-custom-test-harness no vendor
- eval-human-loop no vendor
- eval-production-traffic-replay no vendor
- licensing-bucket open-source repo
- taxonomy-three-layer-rollup agent-infra repo
- developer-activity-opendigger {"activity":38.62,"as_of":"2026-09","openrank_12mo":3.69,"openrank_current":2.42,"partic… third-party
What changed
Changes to this record's lifecycle, licence, release, pricing and hosting facts, from the catalog's git history. Subscribe (Atom)