jif e1831db7c3 Reuse MCP handlers across sampling steps (#37273) ...

## Why

MCP tool handlers and their Code Mode definitions are immutable for the lifetime
of a stable MCP binding, so rebuilding them for every sampling step repeats schema
construction unnecessarily.

## What changed

- Cache MCP handlers per session and reuse them while the same binding remains
  active, invalidating the cache when the binding changes.
- Lazily cache schema-free Code Mode definitions on MCP handlers while continuing
  to rebuild definitions for step-local tools whose specifications may change.
- Reapply current app enablement, tool policy, exposure, and plugin schema budgets
  whenever cached handlers are registered for a step.

## Testing

- Cover handler and Code Mode definition reuse, binding invalidation, changing app
  policy, stable continuation schemas, and step-local custom tool updates.

GitOrigin-RevId: 69c5011fb97c08580ac476e7fb2286b1e92e0359

2026-08-06 13:37:07 +00:00

..

common

Allow injecting model catalog caches (#36992)

2026-08-04 23:04:11 +00:00

remote_env_windows

Scope runtime workspace roots to execution environments (#32952)

2026-07-14 04:41:08 +00:00

suite

Reuse MCP handlers across sampling steps (#37273)

2026-08-06 13:37:07 +00:00

all.rs

[codex] Use expect in integration tests (#28441)

2026-06-15 21:53:47 -07:00

responses_headers.rs

Allow custom providers to opt into standalone web search (#34846)

2026-07-23 00:02:15 +00:00