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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is known. The description adds valuable context about scoping ('Scoped to your identifier (anonymous IP, BYO key hash, or account ID)') and the list-all behavior when the key is omitted, going beyond the structured 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 core action and immediately useful context. Every sentence earns its place: the action, the use case, the scoping, and the companion tools. 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 and no output schema, the description covers the essential aspects: what it retrieves, how to list all keys, the intended use case, scoping, and relationship to remember/forget. It is fully sufficient for an agent to select and invoke the tool correctly.

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 repeats this behavior without adding new semantic details, so it meets the baseline but does not exceed it.

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 pair: 'Retrieve a value previously saved via remember, or list all saved keys.' It clearly distinguishes itself from sibling tools by referencing 'remember' and 'forget' as complementary actions, making the tool's role in the memory workflow explicit.

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?

It states when to use the tool ('Use to look up context the agent stored earlier... without re-deriving it from scratch') and points to related tools ('Pair with remember to save, forget to delete'). It lacks an explicit 'when not to use' exclusion, but the context is clear enough for a simple lookup tool.

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