echo

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

Annotations already declare readOnlyHint=true, idempotentHint=true and openWorldHint=false, so the safety profile is fully covered elsewhere. The description adds nothing beyond restating the echo behavior — no note on output format, size limits, or edge cases such as empty messages.

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?

A single short sentence with no filler, and the core behavior is front-loaded. It is efficient, though so terse that it carries little information.

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 one-parameter, trivially idempotent utility with a fully described schema and complete annotations, this is essentially enough to call it correctly. Only a hint about the intended testing purpose would improve it.

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 description coverage is 100% and the single 'message' parameter is documented as 'The message to echo back'. The description adds no syntax, length, or encoding guidance beyond the schema, so the baseline 3 applies.

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 states a specific verb and resource: it echoes back the input message. That makes the tool's contract unambiguous and clearly distinct from the sibling tools (file_read, file_write, json_transform), though it spends no words explicitly differentiating itself from them.

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?

There is no statement of when to use this tool versus alternatives, no mention of the common use case (connectivity/round-trip testing), and no exclusions. Usage is only inferable from the one-line behavior.

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