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

The annotations already signal read-only and open-world behavior, and the description adds substantial behavioral detail: exactly what fields are returned, the significance score scale with the 8+ exceptional threshold, the presence of source articles and links, and the authentication requirement. It also clarifies the deduplication behavior of clusters, which helps the agent set user expectations.

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 primary purpose and then efficiently covers return values, usage context, input sourcing, and authentication. Every sentence contributes useful information, though it is slightly longer than strictly necessary due to the explanatory cluster concept.

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 single-parameter read-only tool with no output schema, the description is remarkably complete. It covers what the tool returns, how to obtain the required identifier, when to use it, and the access requirements, leaving no critical gap for an agent to call it 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%, so the schema already documents the cluster_id parameter well. The description adds extra semantics by telling the agent where to find a cluster id (search_situations, get_situation_timeline, or clstr.news URLs), which goes beyond the schema's basic type and format info.

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 identifies the operation (get one news event in detail), the resource (a cluster), and explains what a cluster is. It distinguishes itself from the sibling tools by emphasizing single-event granularity versus near-duplicate headlines and by positioning it as the tool for specifics of one event.

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?

The description gives an explicit use case: 'Use this when the user wants the specifics of one event.' It also explains where to obtain the required cluster_id, which is actionable guidance. It does not explicitly state when not to use alternatives, but the context is clear enough that a competent agent can route correctly.

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