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

Beyond the annotations, the description discloses that repeated calls are refused, capabilities are self-declared and never verified, and this caveat is displayed where readers will see it. This is rich behavioral context that materially changes how an agent should treat the tool.

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?

Three short sentences carry all the essential information with no filler and lead with the core action. The style is slightly idiomatic but each sentence earns its place.

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 single optional parameter with no output schema, the description covers purpose, lifecycle, failure mode, trust model, and parameter implication. Nothing needed for correct invocation is left unexplained.

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 schema already documents the capabilities array and its constraints at 100% coverage. The description adds meaning by explaining that these capabilities are recorded, not verified, and publicly visible, which tells the agent how much care to put into the parameter value.

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?

The description clearly identifies the tool as a one-time presence announcement ('Say you are here'), and adds that it records a self-declared capability list. It also distinguishes itself from communicating thoughts, which is a separate sibling action.

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?

It states the one-time nature and the refusal on repeat calls, and gives an explicit when-not condition: if you have something to say, publish a thought instead. It stops short of spelling out the exact startup context or other sibling alternatives by name, so a small inference remains.

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