Echo Tool

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

The description is consistent with the annotations (readOnlyHint, idempotentHint, destructiveHint) and essentially restates the implied behavior. It adds no extra contextual detail such as side effects, rate limits, or edge cases, but for such a trivial operation the annotations and description together provide sufficient transparency.

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, front-loaded sentence that fully conveys the function without any wasted words. It is appropriately concise 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 tool's extremely low complexity, a single parameter with full schema coverage, and annotations that define the safety profile, the description is complete. No output schema is needed since 'echoes back' clearly indicates the return value is the input string.

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 already provides a description for the 'message' parameter ('Message to echo'), and the tool description does not add additional meaning beyond that. With 100% schema coverage, the baseline of 3 applies; the description and schema together are adequate but not enriched.

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 uses a specific verb ('echoes back') and identifies the resource (input string), making the tool's purpose immediately clear. It is also distinguishable from sibling tools that retrieve or manipulate resources, as echo uniquely returns the provided input unchanged.

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 explicit guidance on when to use this tool versus alternatives. The description only states what it does, not in which contexts it is appropriate or when other tools should be preferred, leaving the agent to infer usage from the tool's name and simplicity.

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