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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds behavioral context beyond annotations by explaining the dual behavior (index vs. single operation) and the accepted selector formats (tool name, full path, path suffix). It doesn't describe response format details, but with no output schema and a read-only metadata tool, the description carries enough behavioral context.

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 three sentences with no wasted words. It front-loads the core purpose, then explains the parameter behavior, and ends with a clear usage directive. 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 read-only metadata tool with one optional parameter and no output schema, the description is nearly complete. It explains both invocation modes and the accepted selector formats. It doesn't describe the structure of the returned index or operation details, but the description's promise of 'compact index' and 'full parameters and resolved response schemas' gives the agent enough context to call it and interpret results.

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%, so the schema already documents the `operation` parameter thoroughly. The description adds value by summarizing the parameter's behavior in plain language and by clarifying the three accepted selector formats. It doesn't add much beyond the schema, but the baseline for 100% coverage is 3, and the description's summary of the parameter's optionality and selector flexibility earns a 4.

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: retrieving the Enterprise API's OpenAPI-derived schema catalog. It distinguishes itself from sibling tools by being the meta/schema-discovery tool among the sm_get_* and sm_list_* family, and it explicitly explains the two modes of operation (compact index vs. single operation details).

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?

The description explicitly says when to use this tool: 'Use before calling an unfamiliar tool to confirm its exact fields.' It also explains the two usage modes (omit `operation` for index, pass a tool name/path/suffix for details), which is clear guidance for an agent deciding how to invoke it.

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