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

Annotations already carry destructiveHint=true and idempotentHint=true, so the safety profile is clear. The description's 'Delete' aligns with this but adds only mild context (e.g., clearing sensitive data) beyond what annotations already disclose. No contradiction exists.

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 with zero filler. The first sentence states the action, the second provides usage triggers and sibling pairing. Every word earns its place.

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 tool with a complete schema and annotations covering destructiveness, the description covers purpose, usage, and workflow context. No output schema is needed for a delete action, and the agent can infer the result.

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 fully describes the key parameter as 'Memory key to delete' with 100% coverage. The description's 'by key' adds no new semantic information, so the baseline of 3 is appropriate.

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 opens with a clear verb-object pair: 'Delete a previously stored memory by key.' This directly states what the tool does and distinguishes it from sibling tools like remember and recall, which handle storing and retrieving memories.

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 when-to-use conditions: 'Use when context is stale, the task is done, or you want to clear sensitive data.' It also suggests pairing with remember and recall, which helps the agent understand the tool's role. However, it doesn't explicitly state when not to use it or name alternatives, so it falls short of a 5.

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