Update mail filter

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

The description says 'Replace', which implies full overwrite, but does not elaborate on behavioral traits like whether it performs a complete replacement or merge, or what happens to omitted fields. The annotations (readOnlyHint=false, destructiveHint=false) are present but the description adds minimal context beyond the verb.

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 concise sentence that front-loads the purpose and includes a helpful cross-reference. No waste.

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 complex update tool with nested objects and 7 parameters, the description adequately explains the replacement nature and references the listing tool. It lacks detail on return values (no output schema) and confirmation of full replacement behavior, but is still mostly complete.

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 71%, so the schema provides good parameter descriptions. The tool description does not add additional meaning beyond the schema, meeting the baseline for high 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 clearly states the verb 'Replace' and the resource 'existing mail filter', and references the sibling 'email_filter_list' for obtaining the id. This distinguishes it from create and list tools.

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?

It explicitly says to use an existing filter id from email_filter_list, providing clear context for when to use this tool. However, it does not mention when not to use it or alternatives beyond the listing tool.

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