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

Despite readOnlyHint=true in annotations, the description adds valuable behavioral context: the response format ('Response starts with `Url: ...`') and a specific citation instruction using that exact URL as markdown href. This goes beyond the annotation safety profile.

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 concise sentences plus a formatted example. Every sentence earns its place: first states the purpose, second gives usage sequence and response details, then a labeled example. 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 read tool with one parameter and no output schema, the description covers all necessary aspects: what it does, when to use it, what the response looks like, and how to handle the response correctly. The example completes the context.

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%, so the parameter is fully documented. The description reinforces meaning with a concrete example ('Show me the full page about cost explorer' → { page: ... }), adding usage context beyond the schema but not new parameter semantics.

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 specifies a clear verb ('Retrieve'), resource ('full content of a specific Costory documentation page'), and input method ('by its public docs URL or page path'). It distinguishes itself from sibling tool search_documentation by explicitly stating this is the follow-up retrieval step.

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 usage context: 'Use this after search_documentation returns results.' This clearly indicates when to use the tool in relation to its sibling. The example also demonstrates a natural-language-to-parameter mapping.

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