Explain a PostgreSQL lock mode

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

There are no annotations, so the description carries the full burden. It discloses the core behavior (accepts fragments, explains blocking and acquisitions) but does not detail edge cases such as how ambiguous inputs are handled, whether multiple results are returned, or error behavior. This is adequate for a simple read-only tool but lacks explicit safety or limitation notes.

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 a single, well-structured sentence that front-loads the input condition and clearly states the output. Every word contributes to understanding the tool's purpose and behavior, with no redundancy or fluff.

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), the description sufficiently conveys what the tool does, what input to provide, and what the explanation covers. It lacks details about response format or error handling, but these are not critical for a straightforward explanation tool, making it complete enough for correct invocation.

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 schema provides full coverage of the single parameter 'query' with a clear description and examples. The tool description repeats the same examples without adding new meaning beyond the schema, so it contributes no additional value, meeting the baseline for high schema coverage.

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 action ('explain') and resource ('PostgreSQL lock mode'), and clearly defines the input type (lock mode name or operation fragment) and the output (what it blocks and which operations acquire it). This clearly differentiates from the sibling tool 'analyze_migration', which presumably focuses on migration analysis.

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 implies usage when one needs to know about lock modes, but it does not explicitly state when to use this tool versus alternatives, nor does it mention any exclusions or preconditions. There is no contrast with the sibling tool, so guidance is only implicit.

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