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

Annotations already declare readOnlyHint=true and openWorldHint=true, covering the safety profile, and an output schema documents the return shape. The description adds the useful 'latest' recency framing and enumerates fields, but those largely overlap the output schema, so incremental disclosure beyond structured data 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?

Three short sentences with zero waste; the core purpose leads and the routing hints follow. Nothing needs to be trimmed or reordered.

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 two-parameter read tool with annotations covering safety and an output schema covering returns, the description is nearly complete. The main residual gap is guidance on where valid section slugs come from and how paging behaves.

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%, so both parameters (page, section) are already documented, including the pointer to /ft/categories. The description adds no syntax, format, pagination, or default details beyond the schema, so the baseline of 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?

The description names a specific verb and resource ('Fetch the latest stories in a Financial Times section') and enumerates the returned fields (title, URL, summary, section tag, publication time, lead image). It clearly distinguishes itself from the sibling tools it references. An agent can tell what this produces without opening the 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?

It explicitly routes the agent to alternatives: ft_article for one story's content and ft_news for the general feed. That is clear when-to-use guidance. It omits ft_search and does not state when-not to use this tool (e.g., that it requires a valid section slug from ft_categories), leaving some inference.

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