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

Discloses that storage is key-value scoped by identifier, with persistence details: authenticated users get persistent memory, anonymous sessions retain for 24 hours. Adds beyond annotations (idempotentHint, destructiveHint) by explaining practical 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?

Four sentences, each essential. First sentence states primary purpose, second gives usage guidance, third clarifies behavior, fourth links to related tools. No redundancy.

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 store tool with no output schema, description covers persistence, scoping, and relationships to recall/forget. Agent has sufficient information to use 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%, but description adds valuable examples for key (e.g., 'subject_property', 'target_ticker') and value ('any text — findings, addresses, preferences, notes'), enhancing schema meaning.

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?

Description clearly states the verb 'Save', resource 'data', and context 'the agent will need to reuse later across this conversation or across sessions'. It distinguishes from sibling tools by mentioning recall and forget as complementary operations.

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 tells when to use: 'when you discover something worth carrying forward' with concrete examples (resolved ticker, target address, user preference, research subject). Also states pairing with recall and forget, implying when not to use.

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