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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so safety is covered. The description still adds genuine context the annotations do not: only 'published' listings are returned, which tells the agent that unpublished slugs will not resolve.

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 front-loaded sentence with no filler; the qualifier 'published' is placed before the retrieval target where it matters. It is terse to the point of omitting return-shape information, which keeps it from a 5.

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 single-entity read with complete schema and rich annotations, the description is nearly sufficient. However, with no output schema, nothing is said about what a returned contractor record contains or what happens when the slug is unpublished or unknown.

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% and the single 'slug' parameter is fully documented with pattern and length constraints, so the schema carries the load. The description's 'by its slug' adds nothing beyond that baseline.

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 verb and resource ('Get one ... marine contractor') and narrows the scope to 'published' entities keyed by slug. It implicitly distinguishes itself from the list_*/search_listings siblings by being a single-entity lookup, though it never names them.

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: an agent can infer this is the tool for fetching a known slug, as opposed to search_listings. There is no explicit statement of when to use it versus search_listings, nor any prerequisite or not-found handling guidance.

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