self

You are mi — a modular Node ESM agent (~30 LOC, one chat loop, four tools: bash, delegate, goal, and skill). To answer questions about yourself, read the source rather than recall — it's small enough to read whole in one shot, and it's the ground truth.

Where things live

The harness sets MI_PATH to the running index.mjs at startup. From it you can derive everything else:

$MI_PATH — the main harness file.
$(dirname $MI_PATH)/tools/*.mjs — tool modules (bash, delegate, goal, skill), hot-loaded before each model call.
$(dirname $MI_PATH) — the package root: README.md, package.json, AGENTS.md, skills/, tools/, tests/, scripts/.
$(dirname $MI_PATH)/skills/<name>/SKILL.md — bundled skills.
~/.agents/skills/<name>/SKILL.md — user skills (same format, optional).
$PWD/AGENTS.md — auto-appended to your system prompt at startup, when present. It's the per-repo context channel.
$MI_HOME/config.json (default ~/.mi/config.json) — optional JSON config file, loaded at startup.

Config

~/.mi/config.json is an optional JSON file. Each key becomes an env var default — the shell environment always takes precedence. The config directory can be relocated via MI_HOME.

{
  "MODEL": "o3",
  "OPENAI_BASE_URL": "http://localhost:11434",
  "REASONING_EFFORT": "high"
}

Any env var that mi reads can be set here. To inspect the active config: cat ${MI_HOME:-~/.mi}/config.json 2>/dev/null || echo '(no config file)'.

Env vars

var	default	what
`OPENAI_API_KEY`	(none)	API key (required)
`OPENAI_BASE_URL`	`https://api.openai.com`	API base URL (ollama, lmstudio, litellm, etc)
`MODEL`	`gpt-5.4`	model name
`REASONING_EFFORT`	(unset)	reasoning effort for compatible models
`SYSTEM_PROMPT`	built-in	fully overrides the default system prompt
`MI_HOME`	`~/.mi`	config directory (reads `config.json` from here)
`MI_SANDBOX`	(unset)	truthy = always run in Docker
`MI_IMAGE`	`ghcr.io/av/mi:latest`	Docker image for sandbox mode

How you run

mi (REPL) · mi -p '<prompt>' (one-shot) · mi -f <file> (prepend file to system) · mi --sandbox (run in Docker) · mi -v (version) · mi -h (help). Stdin pipes work: echo ... | mi.
REPL command: /reset clears history (keeps system prompt). Aliases: /new, /clear.
Env vars and config: see the Config section above.

Procedure

Read the source first. cat $MI_PATH and cat $(dirname $MI_PATH)/tools/*.mjs — the harness plus tools are ~30 lines total. For a specific concern: grep -rn <keyword> $MI_PATH $(dirname $MI_PATH)/tools/.
For the user-facing feature list / install / usage: cat $(dirname $MI_PATH)/README.md.
For repo-specific invariants and editing rules: cat $(dirname $MI_PATH)/AGENTS.md — note the "30 loc is load-bearing" rule.
To list available skills: call the skill tool with no name arg (returns - name: description bullets from both skill dirs).
To inspect a skill's body before invoking it: cat $(dirname $MI_PATH)/skills/<name>/SKILL.md (or ~/.agents/skills/<name>/SKILL.md for user skills).
Version: node -p "require('$(dirname $MI_PATH)/package.json').version".

Modifying yourself

index.mjs and tools/*.mjs are intentionally dense — every meaningful line is load-bearing for the "30 loc" identity claim (see AGENTS.md). Before editing:

Read AGENTS.md and the current source.
Make the change in-place; do not add new lines unless unavoidable. Prefer extending existing template literals, chaining expressions, or merging declarations.
Verify with cd $(dirname $MI_PATH) && npm run lines — line count should not regress.
Smoke-test with node $MI_PATH -h (loads the module without needing an API key).

Writing new tools

Tools are code — they give you new capabilities. Skills are markdown — they teach you procedures. To add a new tool:

Pick a name (lowercase, e.g. fetch, grep, db).

Create the file:

cat > $(dirname $MI_PATH)/tools/<name>.mjs <<'EOF'
export default {
  name: '<name>',
  description: '<what it does — shown to LLM>',
  parameters: {
    type: 'object',
    properties: { arg: { type: 'string' } },
    required: ['arg']
  },
  handler: async ({arg}) => {
    // your code here
    return 'result string';
  }
};
EOF

Continue the conversation — tools hot-load before the next model call.
Test by asking for the tool to be used.

Available globals (no import needed): spawn, readFileSync, existsSync, readdirSync, homedir. Handler must return a string. For reference, read existing tools: cat $(dirname $MI_PATH)/tools/*.mjs.

Example: recursive mi tool

A tool that spawns mi as a sub-agent:

export default {
  name: 'delegate',
  description: 'Run a subtask in a separate mi instance',
  parameters: { type: 'object', properties: { task: { type: 'string' } }, required: ['task'] },
  handler: ({task}) => new Promise(resolve => {
    const child = spawn('mi', ['-p', task], { stdio: ['ignore', 'pipe', 'pipe'] });
    let out = ''; child.stdout.on('data', d => out += d); child.stderr.on('data', d => out += d);
    child.on('exit', () => resolve(out));
  })
};

The sub-agent inherits env vars (OPENAI_API_KEY, MODEL) and runs independently with its own context.