@agnishc/edb-token-tracker

Pi extension that tracks per-turn LLM token usage for both the main agent and subagents, writing to Postgres.

Designed to work alongside @agnishc/edb-subagents.

Install

pi install npm:@agnishc/edb-token-tracker

Or load directly in the monorepo:

pi -e ./packages/edb-token-tracker/src/index.ts

Database

Default connection URL:

postgres://pi_token_tracker:pi_token_tracker@localhost:5432/pi_token_usage

Override with either:

export PI_TOKEN_TRACKER_DATABASE_URL='postgres://user:pass@host:5432/dbname'
# or
export DATABASE_URL='postgres://user:pass@host:5432/dbname'

For local development from the repo root:

docker compose -f docker-compose.postgres.yml --env-file .env up -d

Use .env.example as the starting point for .env.

To migrate existing rows from the old SQLite DB:

npm run migrate:token-postgres

The migration reads ~/.pi/token-usage.db by default and skips rows already present in Postgres.

How it works

Source	Event	What's captured
Main agent turns	message_end (pi built-in)	session_id, model, caller="main", turn number, all token types
Subagent turns	subagents:usage (from edb-subagents)	Same fields with caller="subagent", plus agent_id and agent_type

Schema

CREATE TABLE token_detailed (
    id          BIGSERIAL PRIMARY KEY,
    timestamp   TEXT    NOT NULL,                  -- ISO 8601
    session_id  TEXT    NOT NULL,                  -- pi session ID
    caller      TEXT    NOT NULL,                  -- "main" | "subagent"
    agent_id    TEXT,                              -- null for main
    agent_type  TEXT,                              -- null for main
    model       TEXT    NOT NULL,                  -- "anthropic/claude-sonnet-4-..."
    turn_number INTEGER NOT NULL,                  -- 1-based per session
    input_tokens    INTEGER NOT NULL,
    output_tokens   INTEGER NOT NULL,
    cache_read_tokens  INTEGER DEFAULT 0,
    cache_write_tokens INTEGER DEFAULT 0
);

All rows use the parent pi session's session_id, so main + subagent tokens for a session are queryable together.

Example queries

-- Total tokens per session
SELECT session_id, SUM(input_tokens + output_tokens) AS total_tokens
FROM token_detailed GROUP BY session_id ORDER BY total_tokens DESC;

-- Per-model breakdown
SELECT model, caller, SUM(input_tokens), SUM(output_tokens)
FROM token_detailed GROUP BY model, caller;

-- Subagent usage by type
SELECT agent_type, COUNT(*), SUM(input_tokens + output_tokens)
FROM token_detailed WHERE caller = 'subagent'
GROUP BY agent_type;

CLI command

/token-db

Shows total recorded turns, input/output totals, and recent turn history from Postgres.

Requirements

• A reachable Postgres database
• @agnishc/edb-subagents v0.16+ for subagents:usage events

License

MIT