creatixchu
0d1250f743
- gate model selection on steering-placement image carriers from enqueue until their steering/message event publishes; release the gate when an admission ends idle without publication (both behaviorally asserted) - reject session.updateQueue edits carrying non-text blocks at the RPC boundary (queue edits cannot bypass image admission) - extend the durable-directory walk past a first-created DSH_HOME to the deepest pre-existing ancestor - strip Windows-style separators from attachment display names on POSIX - verify attachment reads with a header-only probe (digest already proves the bytes decoded fully at admission); document the read path - make SessionInputShell.addImages refusal observable and keep workspace transfers/composer intake from leaking refused drafts - own ONE recursive image walk (dsh-llm contentHasImage) across apiproxy, pi-ai, compact-basic, and the DeepSeek text-only assertion - drop the redundant canonical-base64 regex and the no-op role read - move AttachmentId/AttachmentError out of types.ts (brand.ts/error.ts); document why AttachmentError does not extend HarnessError - document the hard attachments inject in both consumer READMEs
2.7 KiB
Agent Note: Atomic Web image admission
Status: implemented
English | 中文
Problem
Image prompt admission and session.selectModel each read session modality state across asynchronous model and attachment lookups. Without one ordering boundary, an image prompt could validate an image-capable target while a concurrent selection installed a text-only target, or selection could miss a prompt after inbox dequeue but before its durable message event. Scanning the immutable event log avoided the second race but permanently blocked a text-only selection even after compaction removed the image from current model history.
Decision
Each live Web agent has one private promise chain shared by image-bearing prompt admission and model selection. A failed operation settles its caller normally and leaves the chain usable. Text-only prompts bypass the chain because they cannot change the modality constraint.
The pending-publication set records a queued occurrence at dequeue and a steering occurrence already at enqueue (steering items never enter the queued UI mirror), and retains each until its matching user/message or steering/message event publishes. If admission ends without publishing, the transition to idle retires the entries; inbox discard retires the listed work, and session disposal retires every remaining entry. Model selection checks that set, the queued UI mirror, and Session.deriveMessages(), which is the current model-visible history after compaction.
Provider adapters remain the final enforcement boundary. The host ordering only prevents its mutable route and pending image state from contradicting each other before request assembly.
Alternatives considered
Scan every immutable session event. This catches published images but treats compacted-away content as permanently model-visible, preventing a valid later switch to a text-only route.
Retire the pending mirror at inbox dequeue. Dequeue precedes the durable message append and leaves the exact interval in which model selection can miss both pending and published state.
Serialize every prompt and session mutation. Text-only prompts and unrelated session operations cannot introduce an image requirement. A broader lock would add latency and ownership without closing another modality race.
Consequences
An image prompt and a concurrent model selection have deterministic order, and a text-only target cannot strand an image that has been admitted but not yet published. Selection may wait for an in-flight image admission, while unrelated prompts retain their existing concurrency. Compaction can make a text-only target valid once no pending or derived image remains.