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

Annotations already declare destructiveHint=true and idempotentHint=true, so the description does not need to repeat those. The description adds that the memory was 'previously stored,' implying it only affects existing entries, but it does not disclose what happens on missing keys or whether deletion is reversible. Given the annotations cover the key safety profile, this is adequate but not rich.

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 concise sentences. The first sentence states the core action, and the second gives usage rationale and related tools. Every word earns its place, with no redundancy or filler, and the structure is front-loaded with the primary purpose.

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?

Given the tool's simplicity—one parameter, no output schema, and clear annotations—the description is nearly complete. It explains what, when, and how to use it, and references sibling tools. It omits edge-case behavior like non-existent keys or error handling, but the idempotent hint mitigates the need, making this a solid 4.

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 has 100% parameter description coverage, with the key property described as 'Memory key to delete.' The tool description essentially restates this without adding format, case-sensitivity, or example syntax. Baseline 3 is appropriate since the schema does the heavy lifting and the description adds no meaningful semantic value beyond that.

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 'Delete a previously stored memory by key,' which is a specific verb+resource combination that clearly states the tool's function. It distinguishes itself from sibling tools by explicitly naming remember and recall as complementary operations, making its role in the memory system clear.

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 provides explicit conditions for use: 'Use when context is stale, the task is done, or you want to clear sensitive data.' This clearly indicates when the tool is appropriate. It also mentions pairing with remember and recall, though it does not specify when not to use it or name direct alternatives, 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.