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

Annotations already cover safety (readOnly, idempotent, non-destructive). The description adds valuable behavioral context: memory is scoped to an identifier (anonymous IP, BYO key hash, or account ID) and that omitting the key lists all saved keys. This goes beyond the structured annotations, though it doesn't describe edge cases like key-not-found behavior.

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 three sentences, front-loaded with the core action. Each sentence contributes: function, use case, and scoping/companion tools. No fluff or repetition.

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 tool with one optional parameter, strong annotations, and no output schema, the description provides complete contextual information: purpose, usage, scoping, and relationships to save/delete tools. Nothing critical is missing.

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?

Schema coverage is 100% for the single 'key' parameter, so the baseline is 3. The description adds meaning by explaining the dual behavior: retrieving a specific key vs. listing all keys when omitted, which enriches the schema's brief description.

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 states a specific verb and resource: 'Retrieve a value previously saved via remember, or list all saved keys.' This clearly distinguishes it from sibling tools like remember and forget, and the context of looking up stored agent information is explicit.

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 usage context: 'Use to look up context the agent stored earlier... without re-deriving it from scratch.' It also names alternatives and companions: 'Pair with remember to save, forget to delete,' which clarifies when to use this tool versus related memory operations.

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