echo-server.add

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

Annotations already declare readOnlyHint=false and destructiveHint=true, so the agent knows the safety profile. The description adds no additional behavioral context, but for a simple addition operation this is acceptable.

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 a single concise phrase that conveys the entire purpose without unnecessary words. It is appropriately sized for the tool's simplicity.

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 trivial complexity of the operation, the presence of an output schema, and full parameter documentation, the description is sufficiently complete. No additional information about return values or side effects is needed beyond what annotations and schemas provide.

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?

Both parameters a and b are fully documented in the schema with descriptions 'First number' and 'Second number', achieving 100% schema coverage. The description 'Add two numbers' adds no semantic detail beyond the schema.

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 'Add two numbers' clearly states the tool's purpose with a specific verb and resource. It distinguishes itself from sibling tools like echo-server.echo by specifying the arithmetic operation.

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 does not explicitly state when to use this tool over alternatives or mention exclusions. However, the purpose itself implies it should be used whenever two numbers need to be added, which is a basic implied usage context.

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