icu_add_activity_message

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

While annotations already signal a non-read-only write operation, the description adds that the message is attributed to the authenticated user. However, it does not elaborate on other behavioral aspects like visibility or modifications beyond attribution. With annotations present, this is adequate but not rich.

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—just a few sentences that immediately state the action, provide usage examples, and differentiate from a sibling. Every sentence adds value, and no extraneous information is present.

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 simple write operation, the description provides essential context: what it does, examples, and alternative. The output schema exists to cover return values. It might miss a note on whether the message is private or visible, but overall it is complete enough.

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 input schema covers both parameters with descriptions, achieving 100% coverage. The description adds minimal value, only restating 'note or comment' similar to the schema. 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 action (POST a new note or comment) and resource (on a specific activity). It explicitly distinguishes from the sibling tool icu_get_activity_messages for reading, ensuring no confusion.

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 explicitly says when to use this tool (when user wants to leave a note/comment) and provides concrete examples. It also tells when not to use it and directs to the alternative for reading.

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