## Thinking Path
> - Paperclip is the open source app people use to manage AI agents for
work
> - Agent runs stream their transcripts through per-adapter stdout
parsers into the chat/run transcript UI
(`ui/src/adapters/transcript.ts`)
> - The Cursor CLI (local) streams assistant text as many small `text`
events (often a token or word each), and the parser emitted one
assistant entry per event and trimmed each
> - As a result the chat rendered one bubble per token ("every line a
new token") and dropped inter-token whitespace, making Cursor runs hard
to read
> - The render layer already coalesces consecutive `delta` entries
(`appendTranscriptEntry`), but the Cursor parser never tagged streamed
text as a delta
> - This pull request tags streamed `text` as a delta (without trimming)
so the existing render-time coalescer merges them into one assistant
block, while a `tool_call`/`tool_result` between deltas still breaks the
run
> - The benefit is readable Cursor transcripts with correct spacing and
preserved tool boundaries, with no change to the canonical event stream
(raw view unaffected)
## Linked Issues or Issue Description
No existing public issue — describing the bug inline (per
`.github/ISSUE_TEMPLATE/bug_report.yml`):
**What happened**
In the chat/run transcript, Cursor (local) assistant messages render as
one bubble per token/word, and inter-token spaces are dropped, making
the transcript unreadable. Root cause:
`packages/adapters/cursor-local/src/ui/parse-stdout.ts` (`type: "text"`
branch) emitted `{ kind: "assistant" }` per streamed `text` event
without `delta: true` and trimmed each, so the render-time coalescer
(`ui/src/adapters/transcript.ts`) never merged them and whitespace was
lost.
**Expected behavior**
Streamed assistant text should render as a single contiguous prose
block, with tool calls preserved as boundaries between blocks.
**Steps to reproduce**
1. Run a Cursor (local) agent that streams a multi-word assistant
message.
2. Open the run transcript in the chat UI.
3. Observe each streamed token/word rendered as its own bubble, with
inter-token spaces missing.
**Paperclip version**
Reproduced on current `master` (cutover base `e68188c43`).
**Deployment mode**
Self-hosted, `cursor_local` adapter.
## What Changed
- `packages/adapters/cursor-local/src/ui/parse-stdout.ts`: tag streamed
`text` events as `{ kind: "assistant", delta: true }` and stop trimming,
so the existing `appendTranscriptEntry` coalescer merges consecutive
deltas into one block.
- `ui/src/adapters/cursor-coalescing.test.ts` (new): dual-shape golden
fixtures (Cursor local + cloud) exercising the full render-time
projection via `buildTranscript`.
## Verification
- `pnpm --filter @paperclipai/ui exec vitest run
src/adapters/cursor-coalescing.test.ts src/adapters/transcript.test.ts`
→ **10/10 pass**.
- `pnpm --filter @paperclipai/ui --filter
@paperclipai/adapter-cursor-local typecheck` → **green**.
- The golden fixtures assert the run `text → tool_call → tool_result →
text → consolidated final` renders as exactly **two prose blocks with
the tool between them**, **no duplication** of the consolidated final,
and **inter-token whitespace preserved** across coalesced deltas.
## Risks
- **Low risk.** Pure classification at parse time; the canonical event
stream and the raw view are unchanged — only the "nice" render-time
projection changes. The coalescing logic (`appendTranscriptEntry`) is
pre-existing and already covered by tests. No schema, migration, or
behavioral change outside transcript rendering.
## Model Used
- **Claude Opus 4.8** (Anthropic), extended/high reasoning mode, driven
via the Cursor agent with tool use + code execution. Diagnosis and
fixtures grounded in the repo's actual parser/render code.
## Checklist
- [x] I have included a thinking path that traces from project context
to this change
- [x] I have specified the model used (with version and capability
details)
- [x] I have checked ROADMAP.md and confirmed this PR does not duplicate
planned core work
- [x] I have searched GitHub for duplicate or related PRs and linked
them above (none found)
- [x] I have either (a) linked existing issues with `Fixes: #` / `Closes
#` / `Refs #` OR (b) described the issue in-PR following the relevant
issue template
- [x] I have not referenced internal/instance-local Paperclip issues or
links (only public GitHub references)
- [x] My branch name describes the change
(`fix/cursor-transcript-coalescing`) and contains no internal Paperclip
ticket id or instance-derived details
- [x] I have run tests locally and they pass
- [x] I have added or updated tests where applicable
- [ ] I have updated relevant documentation to reflect my changes (N/A —
no documented behavior changes)
- [x] I have considered and documented any risks above
- [ ] All Paperclip CI gates are green (pending CI run)
- [ ] Greptile is 5/5 with no open P2s, recommendations, or follow-ups
(pending review)
- [x] I will address all Greptile and reviewer comments before
requesting merge
Co-authored-by: Sebastian Heyneman <sebastian@joinnova.com>
Co-authored-by: Cursor <cursoragent@cursor.com>
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