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

Adds significant behavioral context beyond annotations: memory is scoped by identifier, authenticated users get persistent memory while anonymous sessions retain for 24 hours. This durability distinction directly impacts how the agent should trust stored data.

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?

Five short sentences, front-loaded with the primary action. No fluff or redundant information; every sentence earns its place by adding usage, persistence, or companion tool context.

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 two-parameter write tool, the description covers purpose, usage timing, persistence behavior, and companion tools. No output schema is needed, and the description is complete without missing essential guidance.

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 covers both parameters with descriptions and examples (e.g., key format). The description's examples of values ('resolved ticker, target address') reinforce the purpose but do not add new semantics beyond the schema. Baseline 3 is appropriate for high schema coverage.

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 uses a specific verb phrase 'Save data the agent will need to reuse later' and clearly identifies the resource as a key-value store. It distinguishes itself from siblings by naming recall and forget for retrieval and deletion, making its unique role clear.

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?

Explicitly states when to use: 'Use when you discover something worth carrying forward' with concrete examples like 'a resolved ticker, a target address, a user preference'. It also provides companion tool guidance by pairing with recall and forget, which clarifies when to use which tool.

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