Plannotator
annotate agent plans, diffs, and HTML
Details
- External ID
- 48495970
- Source
- HN
- Company
- —
- Product
- Plannotator
- Website domain
- github.com
- Launched
- June 11, 2026
- Cohort
- —
- Upvotes
- 5
- Upvotes percentile
- 0.12568306010928962
- Tags
- —
- Fetched at
- Sept. 7, 2026, 9:26 p.m.
- Updated at
- Sept. 7, 2026, 9:26 p.m.
Description
I started this in January as a hook for Claude Code's plan mode: when it finished planning, instead of approving a wall of text in the terminal, the plan opens in your browser and you could mark it up like a document. Your annotations go back into the agent session.It grew from there. There's now PR-style code review (git, jj, p4, GitHub/GitLab PRs) and annotation for markdown, URLs, and folders. Agents produce a lot of HTML now, so Plannotator renders those artifacts and lets you annotate them too. Nine harnesses are supported: Claude Code, Codex, Copilot CLI, Gemini, OpenCode, Kiro, Droid, Amp, and Pi. Over 100 contributors.Nothing leaves your machine unless you share... which is E2E encrypted: eg. the plan is encrypted in the browser, the server stores ciphertext, and the key lives in the URL fragment.As agents get better, the bottleneck shifts to review before and after agents work (obvious to us all now).Open source, MIT or Apache-2.
Enrichment
- Theme
- Claude integrations and coding agents
- Vertical
- Horizontal
- Function
- Observability & eval
- Audience
- Developer
- AI stance
- AI feature
- Project type
- Commercial product
- Normalized one-liner
- annotation tool for agent plans and diffs
- Manually corrected
- False
Could you build this?
Yes It provides a local web server displaying agent plan text and diffs with standard browser annotation tools, sending user comments back via CLI or MCP hooks.
Discussion
2 comments analyzed.
Competitors
Other products that read as similar to this one — 191 launches clear the similarity bar, closest 8 shown.
Attention rank: #162 of 192 (itself plus its competitors, highest first — normalized so YC and Product Hunt are compared fairly).
Launched 213 days after the earliest competitor.
- Code Review Enviornment for the Modern Era · hn · 2026-07-06 · 5 upvotes · similarity 0.61
- Aura: Agents + Git + Intent Open Source · ph · 2026-07-09 · 174 upvotes · similarity 0.46
- Claudit · hn · 2026-02-11 · 7 upvotes · similarity 0.46
- Git why · hn · 2026-04-11 · 11 upvotes · similarity 0.44
- jj diff review integrated with agents · hn · 2026-05-08 · 5 upvotes · similarity 0.44
- Revdiff · hn · 2026-04-12 · 17 upvotes · similarity 0.44
- Claudescope · ph · 2026-09-17 · 1 upvotes · similarity 0.43
- Session Orchestrator · ph · 2026-09-15 · 2 upvotes · similarity 0.42
Other launches for this product
- No other launches for this product.
Same idea, different domain
Nobody's really built a observability & eval tool for Media & entertainment yet.