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

Annotations already declare destructiveHint=true, readOnlyHint=false, and idempotentHint=true, covering the safety profile. The description reinforces the destructive nature with 'Delete' and adds the context of clearing sensitive data, but does not disclose additional behavioral details beyond what annotations provide, so a baseline 3 is appropriate.

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, front-loaded with the main action, and every clause adds value: the operation, the use cases, and the complementary tools. No wasted 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 simple, single-parameter tool with rich annotations and no output schema, the description is complete. It covers what the tool does, when to use it, and the deletion target, making it self-sufficient for agent invocation.

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 schema provides 100% coverage for the 'key' parameter with a clear description ('Memory key to delete') and an example. The tool description adds no new parameter semantics beyond restating that it operates 'by key,' so the baseline 3 applies per the schema-heavy calibration.

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 by key), and differentiates from sibling tools like remember and recall by explicitly framing the operation as deletion.

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 use cases: 'Use when context is stale, the task is done, or you want to clear sensitive data the agent saved earlier.' It also mentions pairing with remember and recall, but lacks a direct 'when not to use' statement or alternative tool comparison, so it falls just 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.