Fetch article by uid

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

Beyond the annotations (readOnly, idempotent, openWorld), the description adds critical behavioral details: the copyright restriction on the full body and the not_found error for invalid uids. There is no contradiction with annotations.

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 two sentences with no waste. The first sentence front-loads the main purpose and enrichment, the second covers limitations and error behavior. Every sentence is essential.

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 has one parameter and an output schema, the description explains what is returned (enriched fields) and what is not (full body), plus error handling. It is fully complete for an agent to use 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?

The single parameter 'uid' is fully described in the schema. The description adds 'from any feed response', which provides useful context beyond the schema's description. Since schema coverage is 100%, the baseline is 3, and the added context raises it to 4.

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 clearly states the verb 'fetch' and the resource 'article', specifying the enrichment components. It distinguishes this tool from siblings like alphai_news_search by calling it the 'canonical single-article lookup' and noting the intentional absence of the full article body.

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 description implicitly provides usage guidance by stating it is the canonical lookup and that the full body is not served due to copyright, hinting that other tools may be needed for full text. It also explicitly states the error behavior for unknown uids. However, it does not explicitly list when to use or not use alternatives.

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