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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering safety. The description adds valuable behavioral context beyond annotations: scoping to an identifier (anonymous IP, BYO key hash, account ID) and the dual behavior of retrieving a single key vs listing all keys. This goes beyond the schema and annotation baseline, though it doesn't address potential edge cases like empty memory or error handling.

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?

Three sentences, all information-dense with no redundancy. The main action is front-loaded, followed by usage context, scoping, and sibling relationships. Every clause 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 read-only tool, the description covers both operational modes, explains scoping, and situates it within the memory workflow (remember/forget). Given the rich annotations and schema, no critical information is missing. The lack of return format details is acceptable since no output schema exists and the tool's behavior is straightforward.

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 the key parameter described as 'Memory key to retrieve (omit to list all keys)'. The description reinforces this by explicitly stating 'omit the key argument' and provides concrete examples of key values (user's target ticker, address, research notes), which helps the agent understand what constitutes a meaningful key. This adds value beyond the schema alone.

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 specific verb+resource: 'Retrieve a value previously saved via remember, or list all saved keys'. It clearly distinguishes itself from siblings by explicitly referencing remember and forget, making the tool's role within the memory system unambiguous.

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?

Explicit guidance is provided: 'Use to look up context the agent stored earlier — the user's target ticker, an address, prior research notes — without re-deriving it from scratch.' It also names the counterparts (remember, forget) and clarifies the omit-key behavior for listing all keys, giving the agent clear when-to-use and alternative context.

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