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

Annotations already establish that this is a read-only, non-open-world lookup, so the description does not need to restate safety. It adds useful behavioral context: the returned fields, the required attribution when relaying stories, the need to link each x_post_url, and an optional follow action through follow_on_x.

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 front-loaded with the core retrieval purpose and return fields, then adds attribution requirements and an optional cross-tool action. It is reasonably compact, though the optional follow instruction is somewhat peripheral to retrieving a story.

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?

With no output schema, the description usefully enumerates the returned story fields and explains the id format. It also covers an important obligation around attribution, making it nearly complete for a simple read tool, though stronger selection guidance versus get_story would improve it.

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 description coverage is 0%, so the description must explain the lone parameter. It does so by clarifying that 'id' is the X post id and that it is digits, which is meaningful beyond the bare string schema.

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 it retrieves one story by id and lists the fields returned, including headline, summary, time, topic, tickers, canonical URL, and cite line. It distinguishes scope as a single-story lookup, though saying it is 'Same as get_story' blurs why an agent should choose this tool over that sibling.

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 implied by 'One story by id' and the id format, but there is no explicit guidance on when to use this versus get_story, query_stories, latest_news, or other retrieval siblings. The attribution and optional follow instructions are usage-related but do not clarify tool selection.

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