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

Annotations already indicate this is a non-read, non-destructive, idempotent write operation. The description adds useful context: authenticated vs anonymous retention (persistent vs 24-hour), and scoping by identifier. It does not contradict 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 structured with a clear lead sentence, usage guidance, and behavioral notes. It is slightly verbose (e.g., the pairing info could be shorter) but every sentence adds value. It is appropriately front-loaded.

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 simplicity (2 params, no output schema, good annotations), the description covers all relevant aspects: purpose, when to use, persistence model, and pairing with siblings. No gaps are evident.

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 both parameters have clear descriptions. The description adds example key formats and value types (findings, addresses, preferences) but these are already inferrable from the schema. The description does not compensate for missing schema info since none is missing.

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 saves data for reuse later, with specific examples (ticker, address, preference) and contrasts with sibling tools recall and forget. It uses strong verbs ('Save', 'store', 'reuse later') and clearly identifies the resource (key-value memory).

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 indicates when to use the tool ('when you discover something worth carrying forward') and mentions pairing with recall and forget. However, it does not explicitly state when not to use it or provide alternatives for other memory patterns.

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