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

Annotations already declare destructiveHint=true and idempotentHint=true. The description confirms destructive behavior ('Delete... clear sensitive data') but adds minimal extra context beyond the annotations. It doesn't discuss edge cases like missing keys or irreversibility, though annotations cover the core safety profile.

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?

Two sentences, front-loaded with the primary action, no wasted words. The conditional usage guidance and pairing note are concise and add value without clutter.

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 simple one-parameter deletion tool with strong annotations, the description covers the essential context: what it does, when to use it, and how it relates to sibling tools. No output schema is needed for a delete operation, and the schema fully documents the parameter.

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 100% coverage, with the parameter 'key' described as 'Memory key to delete.' The description does not add further semantic detail about the parameter, but the schema is already clear, so a baseline score of 3 applies.

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 tool's function: 'Delete a previously stored memory by key.' It uses a specific verb (delete) and resource (memory), distinguishing it from siblings like 'remember' (store) and 'recall' (retrieve).

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?

Explicitly provides usage context: 'Use when context is stale, the task is done, or you want to clear sensitive data.' Also names related tools to pair with ('Pair with remember and recall'), offering practical guidance for when to use this tool versus alternatives.

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