Models
yoyo uses Anthropic’s Claude models via the Anthropic API.
Default model
The default model is claude-opus-4-6.
Changing the model
At startup:
yoyo --model claude-sonnet-4-20250514
yoyo --model claude-haiku-4-5-20250514
During a session:
/model claude-sonnet-4-20250514
Note: Switching models with
/modelclears the conversation history. This is because different models may handle context differently.
Supported models
yoyo works with any Anthropic model. Cost estimation is built in for these model families:
| Model Family | Input (per MTok) | Output (per MTok) |
|---|---|---|
| Opus 4.5/4.6 | $5.00 | $25.00 |
| Opus 4/4.1 | $15.00 | $75.00 |
| Sonnet | $3.00 | $15.00 |
| Haiku 4.5 | $1.00 | $5.00 |
| Haiku 3.5 | $0.80 | $4.00 |
For unrecognized models, yoyo still works — you just won’t see cost estimates.
Context window
yoyo assumes a 200,000-token context window (the standard for Claude models). When usage exceeds 80% of this, auto-compaction kicks in. See Context Management.