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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the safety profile is covered. The description adds valuable scope context (scoped by anonymous IP, BYO key hash, or account ID) and the fact that values are previously saved via remember, which goes beyond annotations without contradicting them.

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, and every sentence earns its place: behavior, usage, and scope/related tools. There is no redundancy or filler.

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 tool with one optional parameter, no output schema, and strong annotations, this description is fully complete. It covers what the tool does, when to use it, how it relates to remember/forget, and the scoping model, providing the agent everything needed for correct invocation.

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 covers 100% of the single 'key' parameter with a clear description. The description reinforces the omit-to-list behavior and enriches semantics by giving concrete examples of key values (user's target ticker, address, prior research notes), helping the agent understand what kinds of keys to expect.

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 and resource: 'Retrieve a value previously saved via remember, or list all saved keys.' It clearly distinguishes from siblings by explicitly naming remember and forget as complementary operations, making the tool's role 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?

The description states when to use: 'Use to look up context the agent stored earlier... without re-deriving it from scratch.' It also references related tools (remember to save, forget to delete), providing a clear workflow. However, it lacks explicit 'do not use when' conditions, though this is minor given the context.

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