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

No annotations exist, so the description carries full burden. It discloses that this is a write operation to a sensitive credential vault, requires proof of npub ownership, and is free. It states deletion affects only one field without affecting others. While it doesn't elaborate on response or error conditions, it provides sufficient behavioral context for a deletion tool.

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 sentences long, front-loaded with the primary action. It includes the key points (action, safety, cost, auth) without extraneous words. Every sentence adds value, making it concise and well-structured.

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 presence of an output schema (context signal) and full schema coverage, the description explains the core purpose, behavioral implications, and authentication requirement. It doesn't differentiate from similar tools like 'weather_forget_credentials' or detail output, but it is largely complete for a straightforward deletion tool.

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 coverage is 100%, with detailed descriptions for all three parameters. The description adds minimal extra meaning: it ties 'dpop_token' to proof of ownership and 'field' to targeted deletion. This marginally enhances understanding but does not significantly expand on the schema descriptions.

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 'Remove a single patron credential field' and 'Deletes one field from stored credentials without affecting other fields.' The verb (remove/delete) and resource (patron credential field) are specific. It distinguishes from siblings like 'weather_update_patron_credential' (overwrites) and 'weather_forget_credentials' (likely removes all) by focusing on single field deletion without side effects.

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 mentions 'Free' and 'Proof of npub ownership is required,' providing some context for when to use. However, it does not explicitly state when not to use this tool versus alternatives like 'weather_update_patron_credential' or 'weather_forget_credentials.' No exclusionary guidance is given.

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