Echo

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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the safety profile is covered. The description adds useful context beyond that: the output is a verbatim return of the input and the intended purpose is a connectivity or health check, which tells an agent the call is a cheap no-side-effect probe.

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?

Two short sentences, with the core behavior front-loaded and the usage hint second. Nothing is redundant or padded, which is appropriate for a trivial tool.

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, side-effect-free echo tool with no output schema, the definition covers everything an agent needs: the behavior, the sole parameter's role, and a reason to call it. There are no hidden prerequisites or return-shape complexities 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?

There is a single parameter and schema description coverage is 100%, so the schema already explains 'Text to echo back' including the minLength constraint. The description only restates that the passed-in text is returned, adding no syntax or format meaning beyond the schema — the baseline of 3 for high coverage 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 gives a specific verb and resource — 'Return the text you pass in' — so the agent knows exactly what the tool does. It doesn't explicitly contrast with the sibling json_format (which transforms rather than returns input verbatim), so it stops short of full sibling differentiation.

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?

'Use this to confirm a host is actually connected' gives explicit when-to-use guidance tied to a concrete scenario. It does not state when not to use it or name an alternative for related needs such as formatting.

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