fine-grained-tool-streaming changedagents-and-tools/tool-use/fine-grained-tool-streaming
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485485When a `tool_use` content block streams, the initial `content_block_start` event contains `input: {}` (an empty object). This is a placeholder. The actual input arrives as a series of `input_json_delta` events, each carrying a `partial_json` string fragment. To assemble the full input, concatenate these fragments and parse the result when the block closes.
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487Where your SDK provides an accumulator helper (as the Python, TypeScript, Go, Java, and Ruby tabs in the previous example do), it handles this for you. The manual pattern is for SDKs without a helper, or when you want full control over how the input is assembled.
487Where your SDK provides an accumulator helper (as the Python, TypeScript, Go, Java, and Ruby tabs in the previous example do), it handles this for you. Use the manual pattern when your SDK has no helper or when you want full control over how the input is assembled.
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489489The accumulation contract:
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