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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds that only public articles are fetched and that body paragraphs are included, which is modest extra context, but it says nothing about auth, rate limits, or failure on private/dead URLs. Appropriate baseline for a read-only tool with annotation coverage.

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 brief sentences, none wasted, with the core action front-loaded before the routing hints. Every sentence earns its place.

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?

An output schema exists, so return values need not be explained, and annotations cover the safety profile. Purpose and routing are complete; only minor behavioral detail (e.g. what happens with an invalid URL) is absent, which is acceptable for a single-parameter read tool.

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 url parameter is documented as a canonical RTÉ News article URL, so the description adds no further syntax or format detail. Baseline 3 applies when the schema carries the parameter meaning.

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 (Fetch), resource (one public RTÉ News article), and exactly what is returned (metadata and body paragraphs). An agent can distinguish it from the sibling feed/list tools without opening any 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?

Explicitly routes to two named alternatives with the condition for each: rte_headlines for discovering story cards and rte_news for the general feed. This leaves no ambiguity about when to pick this tool versus its siblings.

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