Annotate Last - Plannotator Docs

The /plannotator-last command opens the agent’s most recent response in the annotation UI, letting you highlight text, add comments, and send structured feedback back.

Usage

Claude Code

/plannotator-last

OpenCode

/plannotator-last

Pi

/plannotator-last

Codex

!plannotator last

How it works

User runs /plannotator-last
        ↓
Last assistant message extracted from session
        ↓
Annotate server starts (random port)
        ↓
Browser opens, loads annotation UI
        ↓
/api/plan returns { plan: message, mode: "annotate-last" }
        ↓
User annotates → Send Annotations
        ↓
Feedback sent to agent

Session log parsing

Each harness reads the last assistant message differently:

Harness	Source	Method
Claude Code	`~/.claude/projects/{slug}/*.jsonl`	Parses JSONL session logs, finds last assistant text blocks
OpenCode	SDK	`client.session.messages()` API
Pi	SDK	`ctx.sessionManager.getEntries()` API
Codex	`~/.codex/sessions/` rollout files	Parses JSONL by `CODEX_THREAD_ID` env var

For Claude Code, the parser handles streamed chunks (multiple JSONL lines sharing the same message.id), filters out system-generated user messages, and skips noise entries. If the most recent session log has no assistant messages, it tries earlier logs sorted by modification time.

Annotate-last mode differences

The annotation UI in annotate-last mode works the same as /plannotator-annotate, with minor copy changes:

Copy button shows “Copy message” instead of “Copy plan”
Completion screen says “annotations on the message”
Feedback export is titled “Message Feedback” instead of “Plan Feedback”

Server API

The annotate-last mode reuses the same annotate server endpoints. See the annotate docs.

Environment variables

Same as plan review. See the environment variables reference.