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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the tool's safety is clear. The description adds value by explaining scoping ('scoped to your identifier') and the behavior of omitting the key to list all keys, which is not covered by 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 concise (three sentences) and front-loaded with the core action. Every sentence adds value: purpose, usage guidance, and scoping/pairing. No redundant or extraneous content.

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 the simple nature (one optional parameter, no output schema), the description covers the tool's purpose, usage context, scoping, and relationship with siblings. It provides enough information for an agent to correctly invoke the tool without needing additional details.

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?

The parameter schema has 100% coverage with a description for 'key'. The description adds meaningful context by providing examples of what keys might contain (target ticker, address, research notes), enhancing understanding beyond the schema.

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 values saved via 'remember' or lists all keys when the key argument is omitted. It specifies the verb 'retrieve' and resource 'values saved via remember', distinguishing it from sibling tools like 'remember' and 'forget'.

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 use cases (e.g., retrieving a target ticker, address, research notes) and explains why to use it (avoid re-deriving context). It also mentions pairing with remember and forget. However, it does not explicitly state when not to use this tool or compare it to other siblings.

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