echo

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

No annotations are provided, so the description carries the full burden. It describes the core behavior ('echoes back your input') and purpose ('test tool'), but doesn't disclose potential behavioral traits like whether it modifies data, has rate limits, or requires specific permissions. For a simple test tool with no annotations, this is adequate but not comprehensive.

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?

Perfectly concise with two sentences that each earn their place: the first explains what the tool does, the second explains when to use it. No wasted words, and the information is front-loaded appropriately.

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 simplicity (one parameter, no output schema, no annotations), the description is nearly complete. It explains the purpose, usage, and parameter semantics effectively. The only minor gap is the lack of explicit behavioral details like whether it's read-only or has side effects, but for a test tool, this is acceptable.

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?

With 0% schema description coverage and only one parameter ('message'), the description adds meaningful context by explaining that the tool 'echoes back your input,' which clarifies that the 'message' parameter is the content to be returned. This compensates well for the lack of schema documentation.

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 clearly states the tool's purpose with a specific verb ('echoes back') and resource ('your input'), and distinguishes it from siblings by specifying it's a 'test tool' for verification purposes. It goes beyond the name 'echo' by explaining the testing context.

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 states when to use this tool: 'Use to verify the MCP server is responding correctly.' This provides clear guidance on the tool's intended purpose versus its sibling tools, which appear to be IDE/server management functions.

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