wikipedia_read

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

Since there are no annotations, the description carries the burden of disclosing behavior. It explicitly states that content is truncated to max_chars characters, with a default of 15,000, which is a key behavioral trait beyond what the schema shows. It does not cover error cases, but for a simple fetch operation this is adequate.

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?

The description is three concise sentences, front-loaded with the main purpose. Every sentence adds value: the first states the core action, the second clarifies the title requirement, and the third explains the truncation behavior. No filler or redundancy.

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?

Given the tool's simplicity (2 parameters, no annotations), the description covers the essential aspects: what it does, how to supply parameters, and key output behavior. The output schema exists to explain return values, so that is not the description's job. It could mention error handling for invalid titles, but this is a minor gap.

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 input schema has zero descriptions for its parameters, so the description must compensate. It does so effectively by explaining that 'title' should be the exact article title from wikipedia_search and that 'max_chars' controls truncation with a default. Both parameters receive meaningful semantic context beyond their raw schema definitions.

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 begins with 'Fetch the full plain-text body of a Wikipedia article,' which clearly states the verb (fetch), resource (Wikipedia article body), and scope. This distinguishes it from sibling tools like wikipedia_search (which searches titles) and fetch_webpage (which is not Wikipedia-specific).

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?

The instruction that 'title should be the exact article title from wikipedia_search' provides clear workflow context: first search, then read. While it does not explicitly mention when not to use it or compare with alternatives, the guidance is sufficient for a typical usage scenario.

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