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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds only the unmatched-state hint and says nothing about what a "match" contains, whether multiple matches are returned, or how a missing match surfaces (empty result vs. error).

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?

Two short sentences, the core action front-loaded and the fallback immediately after. Efficient, though the brevity is partly under-specification rather than disciplined concision.

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?

No output schema exists, so the description should explain the shape of a returned match and the unmatched case; it does neither. Combined with an undocumented request_id, an agent cannot call this confidently or interpret the result without trial and error.

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?

There is one parameter, request_id, with 0% schema description coverage, and the description never mentions it. No hint on what a request_id is, whether it is optional (it is not in required), or when an agent should supply one.

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?

It states a specific verb and resource ("Read your Slack match"), but "match" is ambiguous – the sibling set includes slack_status, slack_members_match, slack_member_set and slack_me_test, and the description does not distinguish this tool from any of them. An agent can roughly guess it returns the caller's own linked Slack identity, but the concept is not defined.

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 second sentence gives a fallback path ("If unmatched, use 'Connect my Slack' in the app"), which is useful condition-based guidance. However it points at an in-app UI action rather than the sibling yardstick_slack_connect_link, and there is no guidance on when to prefer this over slack_status or slack_members_match.

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