send_message

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

No annotations are provided, so the description must cover behavioral traits. It only states the action and a prerequisite, failing to disclose important details like success/failure responses, rate limits, idempotency, or whether the message is logged or forwarded.

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?

The description is extremely concise with two short sentences, no filler words. It efficiently conveys the core purpose and a key prerequisite. Could include more info, but it is not verbose.

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?

Given the tool's simplicity (one parameter, no output schema), the description covers the basic action and a prerequisite. However, it lacks information about what happens upon sending (e.g., success message, error behavior, delivery guarantees), leaving the agent with incomplete understanding for invocation.

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% and the parameter 'message' already has a clear description in the input schema. The tool description adds no further semantic detail about the parameter beyond the schema, but the prerequisite 'requires an active tier' is an extra context not tied to parameters. Baseline 3 is appropriate.

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 states the specific action: sending a message to the Run402 developers. The verb 'send' and resource 'message to the Run402 developers' are unambiguous. It also distinguishes itself from the sibling 'send_email' which sends to general recipients.

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?

The description mentions 'Requires an active tier' as a prerequisite, but does not specify when to use this tool versus alternatives, nor does it provide context for when not to use it. No explicit guidance on use cases or exclusions.

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