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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuinely useful non-schema context: the body is broken into paragraphs, headings, list items and tables, and embedded markets expose event/market/selection ids — which tells an agent it can chain into Sportsbook market tools. No detail on pagination, auth or article size limits keeps it below 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?

Two sentences, no filler, and the highest-value information (what you get back, including market ids) is front-loaded before the usage instruction.

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 detail fetch with an output schema and read-only annotations, this covers purpose, input provenance and the shape of the returned content. Nothing an agent needs to call it correctly is missing.

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 'article' parameter is already documented as a slug from fanduel_research_articles, so the description largely restates the schema. It adds the provenance link to the sibling tool but no format or validation detail beyond that, making the 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 and resource ('Get one FanDuel Research article in full') and enumerates the rendered body parts, including embedded Sportsbook markets. This clearly separates it from the sibling list tool fanduel_research_articles without needing to open a schema.

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?

'Use it to read an article' plus 'it needs a slug from fanduel_research_articles' gives a concrete prerequisite and workflow pointing at the sibling that produces the input. It stops short of naming when-not-to-use it or listing other alternatives, so it is clear context rather than full routing guidance.

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