fix(runner): skip parallel_tool_calls default for WebSearch agents on Anthropic - #324
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Tembo CAP renamed the public task route mount with no back-compat alias (tembo/monorepo#9519, deployed 2026-07-16). Since then every agent-change dispatch from TAS has failed: /public-api/task/create now falls through to CAP's Zenstack catch-all, which 400s with {"error":{"message":"invalid request path"}}. Same handler and response shape behind the new mount, so this is only the path. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
… Anthropic Follow-up to the pydantic-ai 2.13.0 upgrade: Anthropic's current web_search tool runs with server-side programmatic tool calling, and the API 400s on tool_choice.disable_parallel_tool_use combined with it as soon as the agent also has a client/MCP tool: 400 tool_choice.disable_parallel_tool_use: true cannot be used with programmatic tool calling The wrapper's sequential-tool-calls default (and any explicit spec value, with a stderr warning) is now skipped for WebSearch agents on Anthropic models. Non-WebSearch agents keep the sequential default. Verified: the WebSearch + sidecar-tool repro that 400'd now completes; 11/11 wrapper tests pass. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
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Follow-up to #322, caught by post-deploy verification: the dogfood run of
competitor-monitoring-digestfailed with a new 400 —On pydantic-ai 2.x, Anthropic's web_search tool runs with server-side programmatic tool calling (code-execution-assisted search). The API rejects
disable_parallel_tool_usecombined with it as soon as the agent also declares a client/MCP tool — which the digest agent does (produce_inbox_item). My #322 smoke test had WebSearch but no client tools, sotool_choicewas never sent and the clash didn't surface.Fix:
build_agentskips the sequential-tool-calls default (and drops an explicit spec value with a stderr warning) for WebSearch agents on Anthropic models. Everything else keeps the sequential default (the Attio rate-limit guard).Verification:
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