Use AGENTS.md for project instructions

AGENTS.md is an emerging open standard for providing project-level instructions to AI agents, backed by OpenAI, Google, Cursor, Sourcegraph, and others. Everruns ships it as a built-in capability that re-reads the file on every turn.

Enable the capability

curl -X PATCH http://localhost:9300/api/v1/agents/$AGENT_ID \
  -H "Content-Type: application/json" \
  -d '{
    "capabilities": [
      { "ref": "agent_instructions" },
      { "ref": "session_file_system" }
    ]
  }'

session_file_system isn’t required, but pairing it with agent_instructions lets the agent edit AGENTS.md itself.

Write the file

Drop a plain Markdown file at /workspace/AGENTS.md in the session:

## Project: Acme API

REST API built with Rust + Axum. PostgreSQL for storage.

## Style

- snake_case for variables and functions
- PascalCase for types
- Keep functions under 50 lines

## Build & Test

    cargo build
    cargo test --all-features
    cargo clippy -- -D warnings

## Architecture

- `src/api/` — HTTP handlers
- `src/domain/` — Business logic
- `src/db/` — Database queries

## Commits

Use conventional commits: `feat(scope): description`

There are no required sections. Write whatever a new contributor would need to know.

How it lands in the prompt

When the capability is enabled, the system prompt is composed top-to-bottom:

AGENTS.md content — project-level instructions.
Capability system prompt additions — tool guidance.
Agent’s base system prompt — the agent’s role.

Project context comes first, so capability and agent prompts can reference it.

Limits and dynamics

Content is capped at 32 KiB (32,768 bytes). Excess is silently truncated.
The file is re-read on every turn. Edits during a session apply on the next turn — no restart needed.
If the file doesn’t exist, the agent operates normally without it.

Other tools’ instruction files

Everruns reads only AGENTS.md. Files like .cursorrules, CLAUDE.md, or .github/copilot-instructions.md aren’t read. If you maintain several, symlink or copy them into AGENTS.md for Everruns.