Post a report

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

Annotations already declare readOnlyHint=false, destructiveHint=false, idempotentHint=false and openWorldHint=false, so the safety profile is covered. The description adds that the artifact lands in a mailbox for the counterpart to read, which is useful delivery context, but it omits whether repeated posts accumulate or overwrite, whether ordering matters, and what confirmation comes back.

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?

Two short sentences, front-loaded with the action and destination before the role-specific rationale. No filler, though the second sentence splits into two clauses that could be tightened.

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?

For a non-idempotent write tool with no output schema, the description covers destination and audience but leaves the agent unsure what happens on repeat calls or how the report is later retrieved (presumably read_reports, which is never named). Adequate but with clear gaps.

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?

The description never mentions title, body, or sender. With schema coverage at 67%, the 'title' parameter has no description anywhere, and the description does nothing to compensate for that gap or to clarify the sender default of 'claude'.

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?

Uses a concrete verb-plus-resource framing ("Leave a report in the mailbox") and clarifies the audience ("the other side to read"), which separates it from read-only siblings like read_reports. It does not explicitly contrast itself with send_message, but the resource (report vs. message) is distinct enough to infer.

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?

Provides directional context: Claude Code uses it to report finished work, Duet uses it for notes. That is real when-to-use signal, but there is no exclusion guidance — nothing says when to prefer send_message over post_report, or whether a report should accompany end_session.

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