Get one development

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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered structurally. The description adds real value beyond that: it discloses the shape of the payload (counts, source_mix, storylines, newest statements) and the pagination contract, including that the cursor is null when there are no more results.

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?

Two sentences, front-loaded with what is returned before the pagination instruction, and no filler. Slightly dense enumeration in the first sentence, but every clause names a distinct returned field.

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 carries the return-value burden and does so adequately: it names the main payload components and the cursor semantics. It does not say how many statements come back per call or what happens with an invalid or unknown topic_id, which leaves a small gap for a single-parameter detail 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 topic_id description already explains the id format, so the schema carries parameter meaning. The description adds one genuinely useful semantic link — that the returned statements_cursor is an input to search_statements — but says nothing new about topic_id itself; 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 opens with a concrete statement of what is returned: 'One development in full', then enumerates the substance (counts, source_mix, storylines, newest statements with outlet and headline). It also disambiguates the 'topic'/'development' terminology that the tool name leaves ambiguous, so an agent can tell this detail-fetch apart from list/search siblings.

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 names a specific alternative and the exact handoff: use search_statements with topic_id and the returned statements_cursor to retrieve older statements. That is a clear, actionable routing rule. What's missing is the entry condition (e.g., 'use find_topics first if you only have a name rather than an id'), so it stops just short of full when-to-use coverage.

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