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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds meaningful context beyond those annotations: the tool is scoped to an identifier (anonymous IP, BYO key hash, or account ID) and that omitting the key lists all saved keys. This enriches the agent's understanding of isolation and behavior.

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, front-loaded with the primary action, followed by a practical usage note and scoping detail. Every sentence contributes new information and there is no 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?

This is a simple tool with one optional parameter and no output schema. The description covers the key behaviors (retrieve by key, list all, scope) and pairs it with related tools. Given the low complexity, the description is fully sufficient for an agent to decide and invoke it 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?

The schema already describes the only parameter ('Memory key to retrieve (omit to list all keys)') with 100% coverage. The description reinforces this by explaining the omit-to-list behavior and giving example keys, but it does not provide new syntactic or format details beyond the schema, so the baseline score of 3 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 opens with a specific verb and resource: 'Retrieve a value previously saved via remember, or list all saved keys (omit the key argument).' It clearly distinguishes itself from sibling tools remember and forget, and provides concrete use-cases like 'user's target ticker, an address, prior research notes.'

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 gives clear context on when to use the tool: 'Use to look up context the agent stored earlier — without re-deriving it from scratch.' It also names companion tools ('Pair with remember to save, forget to delete'), but does not explicitly state conditions for when not to use or contrast with alternatives like deep_research or search_within, so it falls short of a 5.

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