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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false, so the agent knows it's a safe read operation. The description adds useful context: scoping to identifier (anonymous IP, BYO key hash, account ID) and pairing with remember/forget, which goes beyond the annotations.

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, starting with the primary purpose. Each sentence contributes: action, use cases, and scoping/pairing. It is front-loaded and efficient, though slightly longer than minimal.

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 one optional parameter, no output schema, and rich annotations, the description covers all necessary aspects: retrieval vs listing, scoping, and relationship to sibling tools. No gaps are apparent for this simple memory lookup tool.

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% with one parameter described. The description adds value by explaining the behavioral effect of omitting the key (list all keys), which is not in the schema description. This clarifies the dual mode of the tool.

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 retrieves a value saved via remember or lists all keys when key is omitted. It specifies the action (retrieve/list), resource (saved memory), and distinguishes from siblings like remember and forget with concrete examples (ticker, address, notes).

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 explicitly tells when to use the tool: to look up previously stored context without re-deriving it. It also explains the omitting-key behavior for listing. While it does not explicitly state when not to use, the pairing with remember and forget provides sufficient guidance.

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