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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is fully covered without the description. The description does add return-scope context — that a match includes its row, associated payments, and an explanatory reason — which is genuinely beyond the structured fields, but it stops short of noting whether the match must be open or signed off.

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 short, front-loaded fragment with zero filler. It is efficient, though the clipped phrasing borders on cryptic rather than precise.

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 trivial read tool with full annotation coverage and a documented parameter this is a small ask, but the agent still cannot tell how a match_id is discovered (rec_matches, rec_candidates) or what a "row" or "reason" actually mean in this reconciliation domain. No output schema exists, so the description is the only clue about the return shape and it only gestures at it.

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?

Single parameter with 100% schema coverage and an inline format example ("BM-0001"), so the schema carries the load. The description adds no meaning beyond it and never says where match_id values come from.

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?

"One match" signals a single-record fetch and the trailing list ("the row, the payments, the reason") sketches the payload, but the action verb is only implied by the tool name. It does not distinguish itself from rec_matches, rec_match, or rec_candidates, so the agent must infer that this is the detail-view counterpart to the list.

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?

There is no statement of when to call this versus rec_matches (list) or rec_candidates. No prerequisites or exclusions are given, leaving the agent to guess the call sequence.

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