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

Annotations already declare read-only, idempotent, open-world, non-destructive behavior. The description adds useful context beyond that: no key is needed and the full one-tick files are available at specific sample paths named in the answer. It does not discuss rate limits or caching, but the safety profile is already well covered.

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 efficient sentences with the core purpose front-loaded and no wasted text. File path details are useful and placed after the main behavior.

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 read-only sample tool with no output schema, the description explains the return content and file locations well enough to call it correctly. Some output-shape detail, such as what exactly a lane entry looks like, is left implicit.

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 0% and the single tier parameter has no enum or description in the schema. The description compensates by enumerating the allowed plan values (free, builder, pro or max) and linking the tier to the sample output, though it does not explicitly name the parameter.

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 specific resource and scope: a sample for one plan, with per-lane series counts and one aligned 1-minute row of real values. It is clear what the tool returns, though it does not explicitly distinguish itself from siblings such as tilla_tiers or tilla_market.

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 by saying it is a free sample requiring no key, which helps an agent understand when to preview data. However, it gives no explicit when-to-use/when-not guidance or named alternatives among the many sibling tools.

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