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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety burden is largely carried. The description adds genuine context beyond them: what the payload covers (official source, latest stable release, freshness, history coverage) and that an unavailable archive surfaces explicitly via state rather than as a silent failure. It says nothing about auth or rate limits, keeping it from a 5.

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?

Three short sentences, front-loaded with the action and lookup key, then inclusions, then exclusions. Little waste, though the phrasing 'An unavailable archive is explicit in state' is terse enough to be slightly opaque about what state actually names.

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?

An output schema exists, so return shape need not be spelled out, and the description still summarizes the covered fields. Annotations cover the safety profile for this read-only lookup. The only real gap is elaborating the agent_slug contract, which is minor for a single-parameter retrieval 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?

The single parameter has 0% schema description coverage, so the schema documents only its type/pattern, not its meaning. The description partially compensates by framing agent_slug as the identifier drawn from coding_agent_list, but it never explains format constraints or what to do if the slug is unknown. Baseline 3 for a low-coverage single-param tool with partial prose compensation.

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, resource, and lookup key ('Get a coding-agent profile by agent_slug'), and names coding_agent_list as the source of that slug. It also carves out scope against siblings by disclaiming benchmark rankings and subscription prices, so an agent can separate it from benchmark_results, offer_compare, and price_watch without opening their schemas.

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?

Clear context: call this with a slug obtained from coding_agent_list for profile-level detail on a single agent. The exclusions ('does not assert product benchmark rankings or subscription prices') implicitly route to other tools but never names which sibling to use when that data is actually wanted, so it stops short of full when/when-not guidance.

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