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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint. The description adds behavioral context beyond these: scoping to the identifier (anonymous IP, BYO key hash, or account ID), the ability to list all keys by omitting the key argument, and the pairing with remember/forget. No contradictions with 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, front-loaded with the primary action, followed by usage guidance and scoping. Every sentence contributes meaningful information without redundancy or fluff.

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 and no output schema, the description is very complete. It explains the main functionality, lists concrete use cases, clarifies scoping, and ties to related tools (remember, forget). The absence of an output schema does not require additional return-value explanation since the behavior is clearly implied.

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% and the schema already describes the key parameter as 'Memory key to retrieve (omit to list all keys)'. The description adds value by providing concrete examples of what keys might represent (user's target ticker, address, prior research notes), enriching the semantics of the parameter beyond the schema. However, since the schema already covers the core meaning, a 4 is appropriate.

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 uses a specific verb ('Retrieve') and clearly states the resource (values previously saved via remember). It distinguishes itself from siblings by explicitly mentioning 'remember' to save and 'forget' to delete, and explains the dual behavior of retrieving a single value or listing all keys.

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 says when to use this tool: 'Use to look up context the agent stored earlier' with concrete examples (target ticker, address, research notes). It also provides exclusions and alternatives by pairing with 'remember' and 'forget', and notes scoping to the agent's identifier.

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