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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, destructiveHint=false), so the description correctly spends its words on non-obvious behavior: the sign-in prerequisite, that connect_start/connect_verify are free and need one email, and how the session should be passed across a conversation. It does not mention rate limits, response size, or failure modes for an invalid id, which keeps it short of 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?

Three tight sentences with the blocking prerequisite front-loaded, then content, then the usage cue and follow-up. No filler, though the auth clause is heavily parenthetical and could read more cleanly as its own sentence.

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 does its job of naming the return payload ('full normalised record plus the document inventory'). The auth prerequisite, which an agent would otherwise fail on, is covered. The remaining gap is the identifier ambiguity between id and opportunity_id, which is not addressed anywhere.

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 only 50%, and the undocumented half is exactly the pair the agent must choose between: 'id' and 'opportunity_id', both nullable strings with no title-level description and no mention in the prose. The description references the sign-in flow but never says which identifier to supply, when to use one over the other, or what as_units changes beyond the schema's own note.

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 and resource ('get_opportunity' returns the 'full normalised record plus the document inventory') and explicitly distinguishes it from the search path ('a search card is not enough'), which separates it from the sibling search_opportunities. An agent can tell what it gets and why it differs from search without opening a schema.

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?

Gives an explicit when-to-use ('Use before advising on a bid'), an explicit when-not ('a search card is not enough'), and a named follow-up tool ('Follow with read_document for eligibility text'). It also names the prerequisite chain (connect_start, connect_verify) and the exception (already signed in).

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