Put the AG-UI Bots back on a model that answers

[davidmckayv]

Everything the from-scratch gate turned up. All five driven, not reasoned about.

Risk Analyst answered nothing at all

Every question, tools or not. The run reached the server and returned 200; no text ever came back, nothing was logged, nothing appeared. Silence is the hardest failure to read, and it took most of the gate to find.

It is the framework Bot on :4201, not the hand-written one on :4200. I defaulted it to gpt-5.6-terra and inferred the Responses API for it in #168, on the strength of a comment in this repo saying that integration could take 5.6 "one line". I never drove it. Called directly:

gpt-5.6-terra → RUN_STARTED … RUN_FINISHED        (no text)
gpt-5.5       → RUN_STARTED … "Hello" … RUN_FINISHED

Both AG-UI Bots now default to gpt-5.5, each for its own measured reason, written where the default is. The built-in Bots keep gpt-5.6-terra — the one place 5.6 is proven, and where the bug that started all this lived. Setting BOT_MODEL to a 5.6 model still works and still switches the Responses API on by itself.

The router was dead

It sent temperature: 0, which reasoning models refuse outright — "Only the default (1) value is supported" — and this call treats a throw as "not sure". Every routing decision quietly became the default coworker; the roster was never consulted. A question naming Google Drive went to a Bot holding no Drive tools.

A fallback that lands on somebody who cannot answer

Every path into the fallback is a guess. When the message names a system exactly one coworker can reach, it isn't one — the others cannot answer at all. Only when unambiguous, and a confident match still wins.

agent-bot was handed a model it cannot use

Same blanket edit. It now refuses to start on a model whose function tools its endpoint rejects, rather than failing one silent tool call at a time, and it has its own AGENT_BOT_MODEL so the other Bot's model cannot take its tools away.

Two silent-failure classes closed

Its history builder no longer trusts the order it is given: read back from the durable store, a tool result arrives before the call it answers and the call's name is missing — a payload no provider accepts, answered with silence.

joinWithin waited on a detached connect forever. A connect that ignores the detach left the gate shut and every later message waiting on it. Bounded now, with a test that hangs without it.

The gate, end to end

• Drive: an untagged question routes to the coworker holding Drive, searches, reads, and answers with all five proxy metrics and exact targets — 95%, 99%, non-zero, 90%, under 3s — checked against the document read out of band. Source and modified time cited.
• Browser: real Hacker News rendered in the container; both titles match an independent curl exactly.
• Policy: page.host == "example.org" refused, computer.action_refused recorded with the rule, and the Bot says which rule stopped it.
• Built-in Bot: answers on gpt-5.6-terra.
• 1254 tests, lint, format, typecheck clean across every package.