A SMALL TOOL FOR A VERY SPECIFIC HEADACHE

Chat works.
Tools don’t.

Find the frame that broke your agent. Check a captured SSE stream, or compare both sides of a gateway to spot lost tool calls.

In your browser. No uploads. No API key.

Chat Completions · Function tools · Raw SSE body

See a failure that single-stream checks miss ↗

Your stream, under the microscope.

LOCAL ONLY

SSE capture

Open file

DIAGNOSIS

Reports contain check codes, line numbers and counts. No captured text, function names, arguments, IDs or headers.

01 /

Find the first bad frame.

Missing indexes, mixed-up parallel calls, invalid reassembled JSON and incomplete streams get a line number and a next step.

02 /

Catch loss across a gateway.

Two streams can each look valid while a tool call disappears between them. Compare decoded calls, allowing valid ID and index remapping.

03 /

Share the structure.

Download a minimized report for a bug ticket. Your trace stays in this tab; the tool makes no API requests and saves no captures.

FREE TOOL · OPEN SOURCE

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How do I capture a stream?

Save the response body from your existing request with curl -N -o capture.sse. Keep stream:true in that request. Run this in your own terminal; do not paste a request with credentials into this page. Compare two sides of the same request, not two independently generated answers.

A text capture has no timing evidence. This tool cannot measure buffering, latency, model quality or the cause of a timeout.

What does a passing check mean?

Only these structural checks passed for this capture. It is not full API certification or a live client test. This version does not inspect Responses, Anthropic, custom tools, tool schemas, HTTP headers, HAR files or transport timing. A missing terminal marker could mean the capture itself was cut off.

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