## Why
Audio attachments could be dropped from tool outputs and reconstructed thread history, while inline base64 payload size could overstate their model context cost.
## What changed
- Preserve remote and local audio attachments in legacy user-message events and thread history.
- Keep audio from function and custom tool outputs when the model supports it and the output fits the truncation budget; otherwise replace it with an omission marker.
- Estimate inline audio cost from its duration, with a serialized-size fallback for malformed or unsupported data URLs, so compaction and truncation use model-visible cost instead of raw base64 size.
- Replace audio in messages and tool outputs with an explanatory placeholder for models without audio input support.
## Testing
Add coverage for history round trips, dynamic tool responses, modality filtering, duration-based context estimates, output-budget truncation, and remote compaction.
GitOrigin-RevId: 5ed4628850a668f8383b7cd73db71b144cc02cd1
## What changed
- Add `audio` to the model input modalities exposed by the protocol and generated app-server schemas.
- Preserve audio in prompts for models that advertise audio input, and replace historical audio with an omission marker for models that do not.
## Testing
- Cover prompt normalization with and without audio support.
- Extend the model-switching integration test to verify that switching from a multimodal model to a text-only model strips prior image and audio content.
GitOrigin-RevId: c18e47ad602720216303ff9abb5bca4d508391ee
## Why
Audio variants were available in the user-input protocol but were replaced with unsupported-input placeholders instead of being sent to the model.
## What changed
- Serialize audio data URLs as `input_audio` content and convert local `wav`, `mp3`, `m4a`, `webm`, and `ogg` files to labeled data URLs.
- Validate and canonicalize base64 audio before requests, enforce the 50 MiB input limit, and replace invalid, unsupported, or oversized audio with explanatory text.
- Preserve audio attachments when mapping response items back to user-message events and document the app-server input variants.
## Testing
- Add unit coverage for local-file conversion, data URL validation, size and format errors, event mapping, and attachment extraction.
- Add client tests that verify data URL and local audio payloads sent to the Responses API.
GitOrigin-RevId: f72cd6b6e43ab12757eeb47621b1d670594ac7d9
## What changed
- Add remote and local audio variants to core and app-server user inputs, including generated JSON and TypeScript schemas.
- Preserve audio fields when converting app-server inputs and response content into thread items.
- Keep unsupported audio out of model requests, TUI rendering, text extraction, and truncated tool output, using explicit text placeholders where audio is submitted as a model input.
## Testing
- Cover app-server media conversion, unsupported-input placeholders, TUI omission, and tool-output truncation.
GitOrigin-RevId: 16152bf3af674575ce569764a8b472e032e7569d
## Summary
- Preserve the optional namespace on custom tool calls during response
deserialization and app-server replay.
- Use the namespaced tool identifier for streaming argument handling and
tool dispatch.
- Regenerate app-server protocol schemas.
- Add regression tests covering namespace serialization and routing.
## Testing
- Ran affected protocol and app-server test suites.
- Ran the full core test suite; two load-sensitive timing tests passed
when rerun individually.
- Ran Clippy and formatting checks.
- Verified with a local end-to-end app-server replay that the namespace
is preserved through the complete request/response flow.
nhamidi-oai