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

Annotations already declare readOnlyHint=true, openWorldHint=false and idempotentHint=true, so the safety profile is covered. The description adds real value beyond them by disclosing the shape of the payload (summary, key numbers with sources, body sections, FAQs, source list), which matters because there is no output schema. It does not cover failure behavior for an unknown slug, but that gap is modest.

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, front-loaded with the action and resource, followed by a compact enumeration of the return contents. Nothing is padded or repeated.

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 one-parameter read tool with no output schema, the description supplies exactly what is missing elsewhere: the structure of the returned article. Combined with annotations covering safety/idempotency, an agent has enough to call it correctly.

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?

Only one parameter exists and schema coverage is 100%, with the schema itself describing it as 'Insight slug'. The description's 'by slug' restates rather than enriches that, giving no format example or hint on where a slug is obtained. Baseline 3 applies.

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 and resource ('Full insight article by slug') and enumerates what the article contains (summary, key numbers with sources, body sections, FAQs, source list). An agent can distinguish this from the list-style sibling search_insights by the word 'Full', though the description never names the search tool 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: 'by slug' signals this is the detail-fetch step after search_insights returns a slug, but there is no explicit when-to-use, when-not-to-use, or prerequisite statement. The agent must infer the search-then-fetch workflow from the sibling list.

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