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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety is covered. The description adds substantive behavioral context beyond that: results are bounded pages, output spans articles/videos/audio/live/topics, topic hubs are explicitly not articles, and media links point only to BBC landing pages, not streams or transcripts. It omits pagination depth and rate limits, so not a 5.

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 core action is front-loaded in the first clause, followed by result-scope caveats and then sibling routing. Every sentence carries new information with no repetition or filler.

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-value detail is not needed in the description. The description covers scope, result-type caveats, and alternative routing, which is everything an agent needs to call this 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?

Schema coverage is 100% with both parameters fully documented, so the baseline is 3. The description restates that `q` is the query and `page` selects the page but adds no format, length, or range detail beyond the 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?

States a specific verb (Search) and resource (BBC public pages), plus the scope of what is returned ('bounded page of result metadata'). It explicitly names the sibling tools it is not (bbc_article, bbc_headlines, bbc_live) and enumerates result types, so an agent can distinguish it immediately.

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 the agent: 'Use bbc_article for article text, bbc_headlines for news lists, or bbc_live for a text snapshot.' Both the when-to-use and the alternatives are stated, leaving nothing to inference.

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