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10 posts tagged.
Measured on @openai/agents 0.18.0: the built-in client-side tool_search loader matches paths against tool names by exact string equality, and a miss returns zero tools with no error and no warning. The failure arrives one turn later as an error that blames the model.
Measured on @voltagent/core 2.11.0: the first agent call lazily starts three setInterval timers that are never unref'd, so your Node process stays alive forever. Two of them poll 20 times a second. Here is the reproduction, the cause and the fix.
On ai 7.0.116, generateText and streamText run exactly one step by default. Pass tools without stopWhen and the model calls a tool, your tool runs, and you get an empty string with no error. The same package defaults ToolLoopAgent to twenty. Measured on the wire, with the bundle lines that cause it.
The Anthropic provider decides your max_tokens, whether temperature is sent at all, and the whole shape of a generateObject request, from a case-sensitive substring test on your model id. Reproduced first-party on ai 7.0.113 with a local capture server and no real API key.
An MCP stdio server that holds a timer or a pool open does not exit when its client dies. Measured on SDK 1.30.0 and Node 24.8.0: it is reparented to init and keeps running. StdioServerTransport registers no stdin end-of-file listener. Here is the reproduction and the four-line fix.
Agent frameworks build the request for you, then show you a summary of it. Here is a 60-line local server that records the exact JSON body your SDK sends, with no API key, no proxy and no certificate, plus the CI assertion a proxy cannot give you.
Mastra documents that the object key, not the tool id, becomes the name the model sees. It does not document that the key is rewritten first: invalid characters become underscores and the result is cut to 63. The tools array goes through that rewrite. toolChoice does not.
The SDK chooses reasoning.effort and text.verbosity from how your model name is spelled, not from what the model supports. Measured on the wire on 0.18.0, including what it does to a custom gateway deployment name.
A grep bisect tells you when today's code landed, not when the behaviour changed. Here is the argv-capture harness that dates it properly, and the worked example where grepping made a maintainer look wrong and running the versions proved him right.
Since @anthropic-ai/claude-agent-sdk 0.3.257 a malformed hook entry is deleted from settings.json and the rest of the file loads normally, so the hook just never runs. PreToolUse and PermissionRequest are the two exceptions, where the whole file is voided. Bisected against 0.3.252, with a runnable detector.
