Spec Kit is an open-source toolkit for defining software requirements and plans before implementation with an AI coding agent. It is used by developers and organizations following a spec-driven development process.
Borrowing it
Nothing to install: this file belongs to github/spec-kit. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/github/spec-kit/main/AGENTS.mdgit clone --depth 1 https://github.com/github/spec-kitWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/github/spec-kit/agents-md)<a href="https://agentmods.dev/instructions/github/spec-kit/agents-md"><img src="https://agentmods.dev/badge/instructions/github/spec-kit/agents-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/github/spec-kit/agents-md"><img src="https://agentmods.dev/badge/instructions/github/spec-kit/agents-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What 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 5.1 | $0.00740 | $0.00740 |
| Opus 5.5 | $0.00296 | $0.00296 |
| Sonnet 5.5 | $0.00148 | $0.00148 |
| Haiku 4.5 | $0.00074 | $0.00074 |
Grade A, and why
spec-kit 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 22d 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 — 77 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
About Spec Kit and Specify
GitHub Spec Kit is a comprehensive toolkit for implementing Spec-Driven Development (SDD) - a methodology that emphasizes creating clear specifications before implementation. The toolkit includes templates, scripts, and workflows that guide development teams through a structured approach to building software.
Specify CLI is the command-line interface that bootstraps projects with the Spec Kit framework. It sets up the necessary directory structures, templates, and AI agent integrations to support the Spec-Driven Development workflow.
The toolkit supports multiple AI coding assistants, allowing teams to use their preferred tools while maintaining consistent project structure and development practices.
Adding or Updating CLI Commands
Before adding, updating, or reorganizing Specify CLI commands, read Shared Command Application Architecture and Specify CLI Command Architecture. They define the shared operation boundary, command-module naming, private phases, nested command groups, registration ownership, and mirrored tests.
Adding or Updating MCP Commands
Before adding or changing MCP tools for Specify commands, read Shared Command Application Architecture and Specify MCP Command Architecture. They define the shared operation boundary, typed contracts, explicit inventory, side-effect metadata, the local stdio protocol boundary, and mirrored tests.
Adding or Updating Agent Integrations
Before adding or changing AI agent integrations, read Agent Integration Design. It covers delivery routes, output formats, registration, and install/uninstall ownership.
Adding or Updating Workflow Steps
Before adding or changing workflow step types, read Workflow Step Design. It covers registration, validation, execution, resume, and installed step packages.
Testing Executable Behavior
Before changing code or configuration that runs or controls execution without an LLM, read Testing deterministic behavior. Behavioral changes need positive and negative coverage; bug fixes need before-and-after regression evidence.
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.
- 22d ago Changed · +10 lines · +105 tokens per session 190597d5c476
- 1mo ago Changed · +8 lines · +70 tokens per session 562f6fb17479
- 1mo ago Changed · -553 lines · -6,761 tokens per session f6f64377a297
- 1mo ago Changed · +8 lines · +67 tokens per session ea88c971e2d6
- 1mo ago Changed · +1 lines · +133 tokens per session 39d05d8c4709
- 1mo ago Changed · +1 lines · +22 tokens per session 28e999146bde
- 2mo ago Changed · +2 lines · +64 tokens per session 590439ab0bfe
- 2mo ago First seen · 600 lines · 7,040 tokens per session scan A 09e95ebd0a86
spec-kit AGENTS.md is an instructions file published in the GitHub repository github/spec-kit (147,879 stars, last pushed yesterday), licensed MIT. It adds 740 tokens to every session, about $0.0030 per session on Opus 5.5. 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.
spec-kit AGENTS.md compared with instructions from other repositories
| Mod | Type | Stars | Last push | Licence | Scan | Tokens | Works with |
|---|---|---|---|---|---|---|---|
| spec-kit AGENTS.mdgithub/spec-kit | Instructions file | 148k | yesterday | MIT | A | 740 | Codex, OpenCode |
| vscode buildNext.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 9,719 | GitHub Copilot |
| next.js AGENTS.mdvercel/next.js | Instructions file | 143k | today | MIT | A | 7,461 | Codex, OpenCode |
| vscode oss-third-party-notices.instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 5,516 | GitHub Copilot |
| langchain AGENTS.mdlangchain-ai/langchain | Instructions file | 149k | today | MIT | A | 4,680 | Codex, OpenCode |
| vscode copilot-instructions.mdmicrosoft/vscode | Instructions file | 195k | today | MIT | A | 3,093 | GitHub Copilot |
| deepseek-harness AGENTS.mddeepseek-ai/deepseek-harness | Instructions file | 274k | 2d ago | MIT | A | 4,313 | Codex, OpenCode |