Source Intelligence
Sweep 28 Aug 2026 · 00:00Z Build v2.1.250 478 read Stable v2.1.236 Latest v2.1.250 Next v2.1.251 Feeds RSS JSON llms.txt
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DisclaimerUnofficial, and not affiliated with Anthropic. Nearly all of this is read straight out of what ships: npm bundles, captured prompts, published docs. Anthropic's own notes go in verbatim, marked as theirs. The rest is my reading, and every entry carries the strings behind it. If one looks wrong, vote it down and say why.

Prompt capture

SendMessage tool description

27 model strings share this prompt, byte for byte.

v2.1.200 14 lines 728 chars sha256 291283f82b68 Plain text Whole capture

1# SendMessage
3Send a message to another agent.
5```json
6{"to": "researcher", "summary": "assign task 1", "message": "start on task #1"}
7```
9| `to` | |
10|---|---|
11| `"researcher"` | Teammate by name |
12| `"main"` | The main conversation (background subagents only) |
14Your plain text output is NOT visible to other agents — to communicate, you MUST call this tool. Messages from teammates are delivered automatically; you don't check an inbox. Refer to active teammates by name; to address a background agent that has no name (or whose name a teammate holds) — or to resume a completed one — use its `agentId` (format `a...-...`) from its spawn result. When relaying, don't quote the original — it's already rendered to the user.