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

Annotations already declare readOnlyHint=true, so safety is covered, but the description adds genuinely non-obvious behavior: each link object is null when no such link exists, which tells the agent how to interpret an apparently empty result. It stops short of covering the refund-link case that a sibling tool handles.

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?

One front-loaded sentence with the resource first and the two link shapes as parenthetical detail; nothing is padding. The parentheticals are dense but each clause carries return-shape information the agent needs.

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 burden of describing return values, and it does so for portfolioLink and ventureLink including null semantics. It omits any mention of refund links despite get_refund_links being a sibling, so an agent cannot tell whether this tool covers all links or only two of three kinds.

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 single transactionId parameter is fully documented as a UUID in the schema, so the description need not restate it. It adds no meaning beyond the schema for that parameter, so the baseline 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 specific verb and resource ("Read what a transaction is linked to") and enumerates the two link shapes it returns, portfolioLink and ventureLink, with their constituent fields. It does not, however, contrast itself with the sibling get_refund_links, leaving the boundary between link types implicit.

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?

Usage is implied by the read framing: call it when you need to know what a transaction connects to. There is no explicit statement of when to prefer this over get_refund_links or the link_transfer/link_refund mutation siblings, and no prerequisites are given.

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