Plan: GitHub-style PR review comments in the Agent Manager PR panel

Problem

The PR panel in Agent Manager renders every GitHub review thread as one flat, always-expanded card. The card has weak actions and no way to hand a comment to the agent. Nine concrete defects:

1. The unresolve button looks disabled. A resolved card gets opacity: 0.5 on the whole card (pr-panel.css:248), which dims the enabled Unresolve comment button (PRComments.tsx:96). No disabled attribute is ever set, so the control works but reads as dead. This is the reported bug, and dimming is the wrong fix for "this thread is done".
2. Nothing collapses. Every thread, resolved or not, renders its full diff hunk plus its full Markdown body (PRComments.tsx:118-124). On a PR with 20 resolved threads, the 2 threads that still need work are buried behind hundreds of pixels of settled discussion.
3. The actions are not prominent. Copy is one ghost icon pushed into the header row (PRComments.tsx:80), and resolve is a low-contrast bordered text button at the bottom (pr-panel.css:302). The local review comment cards are the opposite: a real action row with a primary send action.
4. A PR comment cannot be sent to the agent. Local diff review comments have Send to chat per comment and Send all to chat for the batch (review-annotations.ts:425-432, DiffPanel.tsx:443-459). GitHub PR comments have no equivalent, so the user copies text by hand and pastes it into the prompt as raw text.
5. Only the first comment of a thread is fetched. comments(first: 1) in PRStatusPoller.ts:492 and the matching parser (am-pr-utils.ts:69-89) drop every reply. The reply usually holds the decision ("agreed, guard it"), so both the UI and any send-to-agent payload lose the important half of the conversation.
6. No outdated state. isOutdated is not queried, so a comment against code that no longer exists looks identical to a live one.
7. Resolve failures are opaque. The bridge drops the real gh error and posts success: false without the error field that the message type already declares (pr-status-bridge.ts:120-130, types.ts:399-405). The card shows Failed to resolve thread. for a permission error, a network error, and a stale thread ID alike.
8. Strings are hardcoded English in a webview that ships 21 locales.
9. createMemo is used for a side effect (PRComments.tsx:23) to reconcile the optimistic state with the poll result.

Reference behavior: how GitHub does it

The target is GitHub's own review-thread model, not a new invention.

Two GitHub affordances are deliberately not copied: the conversation filter dropdown (a 320px inspector panel does not have room for it, and two grouped sections carry the same information), and reply composition (out of scope, see Non-goals).

Proposed UX

Layout

──────────────────────────────────────────────
▾ COMMENTS                       3 unresolved
  ┌────────────────────────────────────────┐
  │  ➤  Send 3 unresolved to agent         │   primary, full width
  └────────────────────────────────────────┘

  ┌────────────────────────────────────────┐
  │ src/agent-manager/gh.ts:42             │   meta row
  │ ┌──────────── diff hunk ─────────────┐ │
  │ │ - const x = 1                      │ │
  │ │ + const x = 2                      │ │
  │ └────────────────────────────────────┘ │
  │ @alice                                 │
  │ This throws when gh is missing.        │   Markdown body
  │ ▸ Show 2 replies                       │
  │ ────────────────────────────────────── │
  │ [➤ Send] [Resolve]        ⧉  ↗  ⇥      │   action row
  └────────────────────────────────────────┘

  ┌────────────────────────────────────────┐
  │ src/pr/PRActions.ts:8       [Outdated] │   outdated: collapsed by default
  │ ▸ @bob  this mutation needs a timeout  │
  └────────────────────────────────────────┘

▸ Resolved (5)

With the resolved group open:

▾ Resolved (5)
  ▸ ✓ @bob    nit: rename this variable
  ▸ ✓ @alice  can we extract this helper?
  ▸ ✓ @bob    good catch, fixed in a9f21c3

Interaction rules

1. Grouping is derived from server state. Unresolved threads render first, then a collapsible Resolved (N) group that starts closed. The section heading keeps the existing N unresolved count.
2. Unresolved threads render expanded, except outdated ones, which render collapsed with an Outdated badge (GitHub parity).
3. Resolved threads render as one-line rows. The row is a <button> with aria-expanded, showing a check icon, @author, and the first line of the body truncated to one line. Clicking it expands the same card the unresolved threads use, with Unresolve in place of Resolve.
4. No opacity dimming on controls. Remove .am-pr-panel-comment-resolved { opacity: 0.5 }. Resolved state is communicated by the collapsed row, the check icon, and a muted Resolved badge. Muting applies only to the row preview text, never to a button.
5. Resolve gives immediate feedback. On success the card leaves the unresolved group and a toast appears: Comment resolved with an Undo action that calls unresolve on the same thread. The resolved group is not auto-expanded, so the panel does not jump.
6. Pending state does not move the layout. Keep the button in place and show its spinner inside it, instead of swapping the whole row for a Loading line as today.
7. Errors stay actionable. Show the real reason, truncated to one line, and keep the button enabled for a retry. Offer Open on GitHub as the escape hatch.
8. Replies are progressive. The card shows the first comment and a Show N replies disclosure. Replies render with the same Markdown component, indented, and are always included in a send-to-agent payload even when the disclosure is closed.

Action row

Order, left to right, always visible (not hover-only, because a hidden action in a narrow inspector is an undiscovered action):

This mirrors the local review comment card, which pairs text buttons for the primary verbs with ghost icon buttons for the utilities.

Bulk send

• One primary, full-width button under the section heading: Send 3 unresolved to agent. It only renders when unresolved > 0.
• When a side terminal is the active destination, the label becomes Send 3 unresolved to terminal, following the same destination rule the diff panel already uses via activeTerminalId.
• Bulk send never resolves anything on GitHub. The agent has not fixed the code yet, so resolving would be a lie to the reviewer.
• Sent threads get a Sent badge for the rest of the session, kept in a per-worktree Set<threadId> in AgentManagerApp, next to the existing reviewCommentsByContext state. Without it, a second click looks identical to the first and silently duplicates the prompt.
• A toast confirms: Sent 3 comments to the agent.
• Payload caps, so one PR cannot blow up a prompt: at most 100 threads (the existing LIMIT in the shared review payload), the diff hunk truncated to 40 lines, each body truncated to 4000 characters, and each thread limited to 10 replies. When anything is dropped, the toast says Only the first 100 comments were sent.

Reuse the existing comment message UI

Do not paste raw text into the prompt. Convert a PR thread into the same review comment payload the local diff review already uses, so the message renders as a comment chip with a detail dialog (ReviewComments.tsx) and survives in session history through the part metadata (review-comments.ts).

The chip gains two PR-specific affordances: a github icon instead of the comment icon, and @author next to the file name. The detail dialog renders the body with the shared Markdown component and shows the diff hunk in the existing snippet slot.

Data model

GraphQL query

Extend fetchComments in PRStatusPoller.ts:478-529:

reviewThreads(first: 100) {
  totalCount
  nodes {
    id
    isResolved
    isOutdated
    diffSide
    resolvedBy { login }
    comments(first: 20) {
      totalCount
      nodes { id author { login avatarUrl } body path line originalLine url createdAt diffHunk }
    }
  }
}

originalLine gives a usable line for outdated threads where line is null. diffSide maps LEFT to deletions and RIGHT to additions, which the review payload needs. Thread pagination stays at 100 with no cursor loop, same as today.

PRComment

Extend the three mirrored declarations (src/agent-manager/types.ts:62-74, webview-ui/src/types/messages/agent-manager.ts, webview-ui/agent-manager/pr/pr-types.ts:16-28):

outdated: boolean
side?: "additions" | "deletions"
resolvedBy?: string
replies?: { id: string; author: string; body: string; createdAt?: number }[]
replyCount?: number   // thread totalCount - 1, so ">20 replies" stays truthful

unresolved count semantics do not change.

Shared review payload

Add a discriminated PR variant to src/shared/review-comments.ts rather than loosening the local shape:

export interface PRReviewCommentData {
  id: string            // GitHub thread node id
  origin: "pr"
  author: string
  body: string
  file?: string
  line?: number
  side?: "additions" | "deletions"
  diffHunk?: string
  url?: string
  outdated?: boolean
  replies?: { author: string; body: string }[]
}

export type ReviewCommentEntry = ReviewCommentData | PRReviewCommentData

Rules that keep this safe:

• version stays 1. An entry without origin follows the existing strict local validation, so every historical message keeps parsing.
• view() compares the message text against Markdown regenerated from parsed data. The PR formatter must therefore be fully deterministic and every PR field must round-trip through parseComment, or old and new messages fail the prefix check and lose their chips.
• file and line are optional only for origin: "pr", because GitHub allows a thread with no resolvable line. The formatter omits the missing fragment.
• Path validation (no absolute path, no .., no NUL) applies to PR entries too. The path comes from an API response, but it still reaches openFile.

Markdown produced for a PR entry:

## Review Comments

**src/agent-manager/gh.ts** (line 42), PR comment by @alice:
```
@@ -39,7 +39,7 @@
-  const x = 1
+  const x = 2
```
This throws when gh is missing.

> @bob: agreed, guard it

A thread with no file or line degrades to PR comment by @alice:.

What was implemented

The change landed as one pass over the files below.

Thread data

The poll deduplication hash now includes a comment signature. Thread and unresolved counts alone do not change when a reply is added or a body is edited, so without the signature the panel would render replies it can never refresh.

resolvedBy and diffSide were not added. Neither is used by the UI or the payload, so fetching them would only grow the query.

Shared review payload

src/shared/review-comments.ts gained a PRReviewCommentData variant of ReviewCommentEntry, guarded by origin: "pr". version stays 1, entries without origin keep the old strict local validation, and every PR field round-trips so the markdown prefix regenerates byte for byte. webview-ui/agent-manager/pr/pr-comment-payload.ts converts a PRComment into that payload with the caps, and also produces the copy text, the collapsed row preview, and the githubUrl guard that keeps non-https urls away from both the payload and openExternal. Hunk truncation keeps the @@ header and the tail, and caps total characters, because a generated file can put a whole hunk on one line and exceed the shared payload limit.

The payload deliberately carries no url and no reply identifiers. Nothing reads them, and unused metadata in a persisted message format only invites drift.

UI

The card owns its collapsed row instead of a separate row component, and replies render inline when a card is open instead of behind a second disclosure. Both choices keep the component count low for the amount of behavior involved.

The list keeps Solid's Index, not For. Each poll allocates fresh PRComment objects, so identity keying would remount every card and repeat the Pierre diff and Markdown work on every status push. Sending reuses the existing sendReviewComments helper instead of a second copy of the event envelope.

Deliberate simplifications

• No toasts and no undo affordance. A successful resolve collapses the card and opens the Resolved group, so the thread is visibly moved rather than gone, and unresolve is one click away inside that group.
• The Sent badge is component-local state, not lifted into AgentManagerApp. It resets when the panel closes, which is enough to stop a double send from looking identical to the first one.
• A failed resolve or unresolve forces the card open, otherwise the error would be hidden inside a collapsed row.

Localization

agentManager.pr.comment.* and agentManager.review.metaAuthor were added to webview-ui/agent-manager/i18n/en.ts and all 20 other locales, which tests/unit/i18n-keys.test.ts and agent-manager-i18n-split.test.ts require.

Edge cases

Tests

Commands: bun run typecheck, bun run lint, bun run test:unit from packages/kilo-vscode/, plus bun run knip because new exports are added.

Non-goals

• Replying to a PR comment or creating a new review comment from the panel.
• Approving, requesting changes, or submitting a review.
• Resolving a thread automatically after the agent edits the code.
• Thread pagination past 100 threads.
• A GitHub-style conversation filter dropdown.
• Reusing the Pierre annotation layer to place PR comments inline in the diff viewer. That is a larger, separate change.

Changeset

One minor changeset: resolved PR comments collapse like GitHub, PR comments can be sent to the agent individually or in bulk, and PR comment cards gain prominent copy, resolve, and open actions.