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

Goes beyond the annotations by describing persistence semantics ('Authenticated users get persistent memory; anonymous sessions retain memory for 24 hours') and scoping ('scoped by your identifier'). The description is consistent with idempotentHint=true and readOnlyHint=false, and adds useful details about data lifetime.

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 compact and front-loaded with the core purpose, followed by usage context, technical details, and companion tool references. Every sentence adds value without excessive verbosity.

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 simple schema (2 required string params) and no output schema, the description fully covers what the tool does, when to use it, storage semantics, and how it relates to recall/forget. No critical missing behavioral information.

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 self-explanatory descriptions for 'key' and 'value'. The tool description does not add parametric meaning beyond giving examples of keys in the usage context, so it meets the baseline but does not exceed it.

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 'Save' with a clear resource ('data the agent will need to reuse later'). It distinguishes from siblings by explicitly naming 'recall' and 'forget' as companions, and gives concrete use examples like 'a resolved ticker, a target address, a user preference'.

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?

Provides explicit guidance on when to use ('Use when you discover something worth carrying forward') and contrasts with alternatives ('Pair with recall to retrieve later, forget to delete'). This gives clear context for choosing this tool over the related memory tools.

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