Chuck, the coding agent
Chuck writes code. It owns shell scripts, scaffolds, logic implementation, debugging, and refactors. Chuck refuses planning work (Echo does that) and escalates hard security, cryptography, and payments work to Sonnet. It balances speed and correctness by choosing the right model tier per task.
Model tiers
| Tier | Trigger | Model |
|---|---|---|
| T0/1/2 Shell, scaffold, simple code | shell or basic logic | GPT-5 Nano |
| T3 Multi-file (queued) | coordinated changes | Kimi K2.5 |
| T3 Multi-file (interactive) | live feedback loop | GPT-5 Nano |
| T4 Complex logic, hard debugging | tricky algorithms or state | Claude Haiku 4.5 |
| T5 Auth, security, crypto, payments | sensitive domains | Claude Sonnet 4.6 |
Escalation
Refuses planning work, Echo handles plans.
Sample
Diff snippet: SQL injection fix
- const user = await db.query(`SELECT * FROM users WHERE email = '${email}'`)
+ const user = await db.query('SELECT * FROM users WHERE email = $1', [email])