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

No annotations are provided, so the description carries the full burden. It usefully discloses the return payload (published plans, derived cost, source URL, read date), which is valuable given there is no output schema, but it says nothing about permissions, rate limits, caching, or freshness guarantees beyond the read date.

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?

A single sentence that front-loads the resource and then the return contents, with zero filler. Every clause earns its place.

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 one-parameter read tool with no annotations and no output schema, the description adequately covers purpose and expected return contents. It is only slightly short of complete because it omits any statement about the read-only nature or when to prefer a sibling 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% and the single 'slug' parameter already includes an example, so the schema does the heavy lifting. The description adds no additional slug format or resolution semantics beyond what the schema provides, making baseline 3 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?

States a specific verb (Get) and resource (published plans / USD-per-unit cost) scoped to 'one service', which implicitly contrasts with the multi-service siblings like compare_services and list_indexed_services. It is clear what the tool returns, though it never names an alternative sibling explicitly.

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?

Usage is only implied via the phrase 'for one service', which signals single-service lookup rather than comparison or listing. There is no explicit when-to-use clause, no mention of alternatives like compare_services or get_cheapest_by_category, and no stated prerequisites.

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