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

Annotations already declare readOnly=true, idempotent=true, non-destructive=true, and closed-world. The description adds only the connectivity-verification context, which is useful but modest; it does not describe return behavior or any rate/size constraints beyond what annotations and schema imply. With this annotation coverage, a 3 is appropriate.

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 zero waste, and the core action is front-loaded before the usage restriction. Every sentence 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 trivial, single-parameter, read-only diagnostic tool with full annotation coverage and a complete schema, nothing an agent needs in order to call it correctly is missing. No output schema is required for an echo operation.

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 'text' parameter is fully documented in the schema (min/max length, meaning). The description adds no parameter detail beyond the schema, so the baseline 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?

States a specific verb (echo) and resource (input text) and defines the scope precisely: it returns the caller's own text. This is unmistakably distinct from the six vehicle/listing search siblings, so an agent can tell them apart without opening any schema.

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?

Explicitly restricts use to verifying MCP connectivity, which tells the agent both when to use it (connection checks) and when not to (any actual data task). The word 'only' is a clear exclusion, and no alternative sibling is needed for this diagnostic purpose.

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