deepseek-harness/.agents/notes/implemented/simplification/2026-07-31-web-ui-no-steer-entry-or-interjection-chrome.md

Agent Note: Web UI drops steer entry and interjection chrome

Status: implemented

English | 中文

Problem

Mid-turn steering is a host/agent-loop capability (mode:'steer', a durable user/message). The Web product already locked the composer while a turn runs and never shipped a queue/steer menu, yet the client still threaded 'queue' | 'steer' through the input machine, conversation.send, and locale keys, and rendered consumed steering as a badged 「插话」/「Interjection」 bubble. That left a half-built UI surface: an unused submit mode, a product label for a gesture users cannot perform, and e2e goldens that pinned chrome the product does not own.

Decision

Keep host and runtime steering intact. Remove only the Web UI entry and chrome:

• InputMachine / SessionInput / InputActions.submit / hub defaultSink are queue-only; they always call session.prompt(..., 'queue').
• ConversationService.send(text) drops its mode argument and always queues.
• Durable steer content renders as a plain right-aligned bubble (no badge, no user IconActions) so external/host steers stay visible on replay.
• Delete message.steering locale strings and the unused badge CSS.
• The web steering e2e still POSTs mode:'steer' over /api/session.prompt and asserts durable + model-visible obedience; it no longer expects interjection chrome. Update web input machine note fact lines to match.

Alternatives considered

Delete host steering entirely. Out of scope; the user asked only for Web UI display and entry. Agent-loop drain, session events, and the wire mode remain load-bearing for ACP/TUI/automation.

Hide durable steer user/message content from the transcript. Would lie on replay when an external client steers; rejected in favor of a plain bubble.

Keep the mode parameter but only ever pass 'queue'. Leaves dead API surface and tests that invent 'steer' paths the composer cannot reach.

Consequences

• Superseded in part. Decision bullets 1 and 3 through 5 no longer describe master: composer steering shipped later, and the context-source and steer marks decision owns its caption. The current facts follow.
• Host steering ownership is unchanged: agent-loop drain, session events, and the wire mode remain load-bearing for ACP, automation, and non-Web clients.
• ConversationService.send(text) still takes no mode and always queues; the composer's Steer gesture uses session.prompt(mode: 'steer') instead.
• Durable steer user/message content still folds into the transcript, so an externally submitted steer stays truthful on replay. It now carries the interjection caption instead of rendering as a bare bubble.
• Non-user next-step items (agent.inject context: approval notices, task completion, attached snapshots) broadcast with the context placement and never render as pending steering bubbles; they stay invisible until claimed as durable user/message context cards.

Testing

• packages/client/ui-conversation unit/jsdom coverage: input machine enter/sink, ConversationService routing, the MessageItem steering arm, InputBar submit.
• apps/web/tests/steering.e2e.ts keyless replay plus its goldens, which pin the caption.
• packages/host/apiproxy session/queue projection test asserts user-origin next-step items stay steering while plugin-origin items land as context.