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

With no annotations provided, the description carries the full burden. It discloses the core check behavior and configurable threshold, but does not explicitly state that it is read-only, what it returns (e.g., a status, boolean, or age), or how it behaves when no symbol is provided (checks overall feed). The purpose is clear, but some behavioral details are missing.

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 two sentences long and front-loaded with the primary action, followed by the rationale and configuration option. Every sentence earns its place, with no filler or repetition.

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?

The tool is simple (two optional params, no output schema), and the description covers the core functionality and purpose. It communicates the tri-state result ('current, stale, or expired') and the configurable threshold, which is sufficient for basic usage. A minor gap is the lack of explicit return format, but this is not critical for this simple tool.

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 description coverage is 100%, so both parameters are already documented. The description adds only a slight contextualization of max_age_seconds ('Configurable max age threshold'), but does not provide additional meaning beyond the schema. Baseline of 3 is appropriate.

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 states a clear verb ('Check') and resource ('data'), and specifies the three possible outcomes: current, stale, or expired. It also explains the tool's purpose ('Prevents agent decisions based on outdated information'), which distinguishes it from the verification-focused sibling tools.

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 implies usage when data age is a concern ('Prevents agent decisions based on outdated information') and mentions a configurable threshold, but it does not explicitly state when to use this tool over alternatives or provide exclusions. There is no reference to sibling tools or conditions that would make the tool inappropriate.

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