Inferred catalog schema

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

Annotations already declare the operation safe via readOnlyHint, openWorldHint, idempotentHint, and non-destructiveHint. The description adds value by revealing that the schema is inferred from the records themselvesans, so its shape is data-dependent, and by detailing the returned content beyond what annotations express.

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 two tight sentences with no filler. It front-loads the concrete field inventory output before the usage directive, making the purpose immediately obvious.

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 zero-parameter, read-only introspection tool, the description fully covers what the tool returns, when to call it, and how the schema is derived. Annotations cover side-effect safety, so no operational detail is missing.

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 tool has zero parameters, so parameter semantics are trivially satisfied; there is nothing for the description to elaborate. The baseline of 4 applies because no parameter documentation burden exists.

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 states a specific verb and output: 'field inventory inferred from the records themselves' and enumerates exactly what is included (type, coverage, numeric min/max, sample values). This clearly distinguishes it from siblings like catalog_stats or catalog_values, which serve different analytical purposes.

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 phrase 'Call this first when exploring an unfamiliar catalog' provides explicit when-to-use guidance and establishes the tool as the initial exploration step. It does not explicitly name sibling alternatives, but the sequencing instruction is clear enough for routing.

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