clear_index

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

Beyond the 'destructiveHint' annotation, the description details that the deletion is from disk, irreversible, and all indexed metadata and search history are lost. It also clarifies what is not affected (in-memory caches), adding valuable 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 concise with three sentences: first states the action, second gives usage guidance, third clarifies limitations and alternatives. No unnecessary words.

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 tool with destructiveHint annotation and no output schema, the description is complete. It covers purpose, usage, effects, and distinguishes from siblings.

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 input schema has no parameters, so the baseline is 4. The description does not need to add parameter info and appropriately focuses on the tool's operation.

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 'Delete' and the resource 'persistent SQLite mailbox index', and distinguishes itself from sibling 'clear_cache' by explicitly noting that it does not clear in-memory caches.

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 gives explicit guidance on when to use ('only to reset a corrupted or schema-incompatible index') and what to do after ('After clearing, call sync_emails to rebuild'). It also points to alternative 'clear_cache' for in-memory caches.

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