Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/ainetx/fdd/agents-mdgit clone --depth 1 https://github.com/ainetx/FDDWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.01040 | $0.01040 |
| Opus 5 | $0.00520 | $0.00520 |
| Sonnet 5 | $0.00208 | $0.00208 |
| Haiku 4.5 | $0.00104 | $0.00104 |
Grade A, and why
FDD AGENTS.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 124 lines — stays where its author put it; the contents beside it link to each section on GitHub.
FDD AI Agent Navigation
Version: 1.1
⚠️ MUST Instruction Semantics ⚠️
MUST = MANDATORY. NOT optional. NOT recommended. NOT suggested.
ALWAYS = MANDATORY. Equivalent to MUST. Used for action-gated instructions.
If you skip ANY MUST instruction:
- 🚫 Your execution is INVALID
- 🚫 Output must be DISCARDED
- 🚫 You are NOT following FDD
One skipped MUST = entire workflow FAILED
All MUST instructions are CRITICAL without exception.
Agent Acknowledgment
Before proceeding with ANY FDD work, confirm you understand:
- MUST = MANDATORY, not optional
- Skipping ANY MUST instruction = INVALID execution
- INVALID execution = output must be DISCARDED
- I will read ALL required files BEFORE proceeding
- I will follow workflows step-by-step WITHOUT shortcuts
- I will NOT create files without user confirmation (operation workflows)
- I will end EVERY response with a list of FDD files read while producing the response, why each file was read, and which initial instruction triggered opening each file
By proceeding with FDD work, I acknowledge and accept these requirements.
Navigation Rules
ALWAYS open and follow workflows/AGENTS.md WHEN receiving any task request
ALWAYS open and follow requirements/extension.md WHEN you see Extends: {file}
ALWAYS open and follow requirements/core.md WHEN modifying any FDD core files
ALWAYS use fdd adapter-info skill to discover FDD-Adapter location WHEN starting any FDD work
ALWAYS open and follow {adapter-directory}/AGENTS.md WHEN starting any FDD work
ALWAYS open and follow requirements/FDL.md WHEN you see FDL
ALWAYS open and follow requirements/workflow-selection.md WHEN selecting which workflow to execute
ALWAYS open and follow requirements/execution-protocol.md WHEN executing any workflow (FIRST)
ALWAYS open and follow requirements/workflow-execution.md WHEN executing any workflow
ALWAYS open and follow requirements/core-workflows.md WHEN creating or modifying workflow files
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 124 lines · 1,040 tokens per session scan A b72b00fa2945
FDD AGENTS.md is an instructions file published in the GitHub repository ainetx/FDD (5 stars, last pushed 7mo ago), licensed MIT. It adds 1,040 tokens to every session, about $0.0052 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
next.js AGENTS.md
Instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.