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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, and the description does not contradict these. It adds meaningful behavioral detail: the record includes recipient org, ABN, address, funding agency, dates, selection process, flags, and the conditional fetching/inlining of a linked grant opportunity when go_id exists. This goes beyond the annotation safety profile, though it does not discuss error handling or rate 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 description is a single dense sentence that efficiently enumerates the record contents and the conditional inlining behavior. It is front-loaded with the core purpose and then details the return fields. While lengthy, every clause adds value and there is no fluff. It could be split for readability, but it remains appropriately sized for the tool's complexity.

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 must carry the full burden of explaining return values. It does so comprehensively: recipient organisation with ABN/address, funding agency, PBS program, grant program/activity, purpose, AUD value, dates, selection process, location, flags, and the linked grant opportunity when available. This makes the tool's behavior fully predictable for an agent, even without an output schema.

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% — the schema already documents ga_id with an example and the 'bare number accepted' rule. The description restates the parameter name and example but adds no new semantic information beyond what the schema provides. Therefore, baseline 3 is appropriate.

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 'Full record for one awarded Australian Commonwealth grant, looked up by its GrantConnect award id', providing a specific verb (looked up) and resource (awarded grant record). It clearly distinguishes itself from sibling search tools (au_grants_search, au_grants_by_recipient) by focusing on ID-based lookup and enumerating the exact fields returned, leaving no ambiguity about what the tool does.

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 clearly implies the use case: when you have a specific grant award ID (ga_id) and need the complete record. It explains that the tool fetches a single record by ID, and the conditional inlining of the linked opportunity when go_id is present adds context. However, it does not explicitly state when not to use it or name alternative tools for searching, so it falls short of a 5.

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