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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds useful context about scoping ('Scoped to your identifier (anonymous IP, BYO key hash, or account ID)') and the optional key behavior for listing. This goes beyond what annotations provide 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, each serving a distinct purpose: action, use case, and scoping/relations. There is no redundant fluff, and the most critical information (retrieve/list) is front-loaded in the first sentence.

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, the description covers the essentials: functionality, use case, and identifier scoping. It could mention the return value format or behavior for missing keys, but these are minor gaps given the tool's simplicity and the presence of annotations.

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% with the 'key' parameter described as 'Memory key to retrieve (omit to list all keys)'. The description adds real-world examples of what keys might contain ('target ticker, an address, prior research notes') and reinforces the omit-to-list behavior, enriching the schema's basic description.

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 a saved value or lists all keys, with specific verb+resource ('Retrieve a value previously saved via remember, or list all saved keys'). It distinguishes itself from siblings by explicitly pairing with remember and forget, making its role in the memory toolset 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 gives explicit use cases ('look up context the agent stored earlier — the user's target ticker, an address, prior research notes') and mentions complementary tools (remember, forget). However, it lacks explicit 'when not to use' guidance beyond implying not to re-derive information from scratch.

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