Receive peer messages

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only cover readOnlyHint and openWorldHint; the description supplies the parts the agent cannot infer: fetch is not an acknowledgement, retained messages repeat when no cursor is given, identity comes from the host rather than a receiver parameter, and the call returns enabled:false when unconfigured. These are genuinely important behavioral facts beyond the annotation set.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Six short, front-loaded sentences with no filler; the scope statement comes first, then the cursor/dedup contract, then the semantic boundaries. Every clause carries actionable information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Covers the tricky cases (unconfigured inbox, repeated messages, non-acknowledgement) for a two-parameter read tool, and the input schema handles limit/cursor. With no output schema, the description could say more about the shape of returned messages, which is the only remaining gap.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so the baseline is 3; the description earns an extra point by explaining what the cursor actually does — that omitting it causes repeats and that its value must be persisted across polls for a given receiver generation. It says nothing about limit beyond the schema's own 1 MiB cap note.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource: fetch eligible messages from this session's operator-configured strict pull inbox. The word 'pull' and 'receive' framing cleanly separates it from send_peer and message_log without needing to name them.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explains the polling contract precisely — pass next_cursor on the next poll, deduplicate by message ID, persist the cursor in durable task state — and bounds the tool with 'does not wake idle sessions' plus a note that peer messages cannot authorize inbox administration. It stops short of naming an alternative tool for admin or log-inspection tasks, so it falls just below explicit when-not/alternatives routing.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.