UI Parser Contract

Adapter UI Parser Contract

Paperclip streams adapter stdout to the run viewer in real time. If your adapter emits structured lines, ship a UI parser so the viewer can render tool calls, tool results, thinking blocks, and system messages instead of treating everything as plain assistant text.

Use this page when:

you are building an external adapter your runtime emits structured stdout you want the run viewer to show more than a shell transcript

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What It Solves

Without a custom parser, the UI falls back to the generic shell parser. That means:

tool invocations appear as plain text tool durations and results are lost stderr and system markers are harder to distinguish

With a parser, the run viewer can render a richer transcript and keep the execution story readable.

> Tip: If your runtime only prints plain text, you can skip the parser entirely and let the generic shell parser handle it.