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

Beyond the readOnly/idempotent annotations, the description discloses important behavior: the returned description is capped at 12,000 characters, descriptionCoverage reports truncation and returned length, and without an mcp-session-id a compact description is returned instead. It also notes the call does not count toward monthly searches, adding useful context about side effects and limits.

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 main function is front-loaded in the first sentence, and subsequent sentences cover genuinely needed edge cases such as truncation and sessionless behavior. It is somewhat dense around the sessionless workflow, but every sentence contributes necessary usage or behavioral information.

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 compensates by explaining what the response contains (description text, descriptionCoverage), how to detect truncation, how to retrieve the full text, and the ID requirement. Nothing an agent needs in order to invoke this tool correctly appears to be missing.

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 description coverage is 100% and the schema already specifies that id must be the exact opportunity ID from search results in CUID format. The description repeats and emphasizes this instruction, but does not add materially new parameter semantics beyond what the schema already provides.

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 begins with a specific verb and resource: 'Get details for a specific funding opportunity.' It clearly distinguishes this from sibling search/list tools by framing it as the targeted per-opportunity detail lookup, and it is not easily confused with get_foundation or other sibling tools.

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 clear usage context: use the exact id from search results, do not construct or guess IDs, and handle truncation by consulting the source URL or echoing the header for the full text. It does not explicitly name alternative tools or exclusion criteria, but the one-parameter prerequisite is stated strongly.

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