Get a Redmine issue relation

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

Beyond the annotations, the description discloses authentication expectations ('ordinary API authentication'), visibility constraints on both linked issues, possible HTTP 401/403/404 outcomes, and preservation of Redmine's null/omitted delay. It also states that no data is changed, reinforcing the read-only annotation. No contradiction with annotations exists.

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 leads with the purpose, then quickly covers the required parameter and behavioral caveats. It is organized and mostly economical, though the final 'never changes Redmine data' sentence largely duplicates the readOnlyHint/destructiveHint annotations.

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 one well-constrained parameter and an output schema present, the description covers the remaining operational context: visibility rules, auth, error codes, and result contents. It is complete enough for an agent to decide whether to call the tool and to know what to expect.

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%, so the schema already documents relation_id as a positive integer with bounds. The description adds little beyond the word 'safe' and the requirement that the ID be a positive numeric ID; no parameter semantics are missing.

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 ('Read'), a precise resource ('Redmine issue relation'), and the exact endpoint ('GET /relations/:id.json'), plus the scope 'one visible ... for the configured API user.' The singularity of the resource and endpoint distinguish it from listing siblings such as list_issue_relations, even though that sibling is not named.

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 sets the invocation context: use this tool to read a single, visible issue relation by relation_id for the configured API user. It also notes there are no query controls and that visibility is enforced for both linked issues. It does not explicitly name alternatives like list_issue_relations for multi-result needs, so it stops short of the strongest usage guidance.

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