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

With no annotations provided, the description carries the behavioral transparency burden. It clearly states the primary behavior—returning the provided text to the caller—and implies a pure, side-effect-free operation. For a trivial echo tool, this is sufficient even without mentioning permissions or side effects.

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, well-structured sentence with no filler or redundant information. The behavior is front-loaded and the entire description earns its place.

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 description is complete. It states what the tool does, what it returns, and to whom, leaving minimal ambiguity for an agent.

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%: the 'text' parameter is already documented as 'Text to echo back'. The tool description essentially restates this, adding no new semantic detail, so the baseline score of 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 uses a specific verb ('Echoes'), a clear resource ('the provided text'), and the recipient ('to the caller'). This makes its function immediately obvious and distinguishable from the sibling tools add and server_time.

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?

Usage is implied by the tool's simple purpose: an agent would use it when it needs to return the same text to the caller. However, the description does not explicitly state when to prefer this tool or contrast it with the sibling tools, though the alternatives are unrelated in function.

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