0.9.121

Two follow-ups to the Pi extension's agent tool from 0.9.120, and a fix to the live Pi suite.

The agent tool's subagent_type description now lists each type with the description: from its agent file, as Claude Code's Agent tool does, so a model can tell when to use a type from pstack-agents. A description: on one line or as a YAML | or > block, as Claude Code agent files often write it, reads as its text. general-purpose shows Claude Code's description of its built-in type (#371).

When an agent file supplies the model or effort, only an error about that value now starts with the file's path. A models.json that cannot be read keeps its own message instead of reading as the agent file's fault (#370).

The live Pi suite's panel test no longer requires opus, fable, and sonnet to map to three different models. The openai and openai-codex tables map opus and sonnet to the same model, so the test failed on those providers (#369).