Source Intelligence

DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

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Claude Code v2.1.227

Unbuffered streaming of partial assistant output

Under the hood
Useful2 Signal2
Elsewhere

Partial assistant output can stream event by event instead of in batches when the flush interval is zero.

What

When the stream flush interval is set to zero, partial output is sent event by event instead of in batches. Consecutive pieces of the same kind on the same content block are merged together up to a byte budget, and any single event larger than the 61440-byte frame budget is dropped. Whether the zero interval is ever used in practice is set outside this code.

Details
  • Merging covers text, tool-input JSON and thinking increments; for thinking, the token estimates are summed.
  • The merge budget is the frame budget minus 4096 bytes.
  • Dropped oversize events are recorded as oversize_ephemeral_skipped.
Evidence

oversize_ephemeral_skipped

Strings lifted out of the shipped bundle, so the claim above can be checked against them.

See this entry in the whole of v2.1.227 →