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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=true, and the description adds meaningful context beyond them: partial update ('only the fields you pass'), reversibility ('old values can be put back'), no recipient notification ('reaches nobody'), and that invoices already created are unaffected. Auth requirement is also stated. Adds real value over the structured fields.

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?

Short, front-loaded sentences, each carrying distinct information (scope, partial-update, inactive, reversibility, side effects, auth). Slightly muddled phrasing in the 'reaches nobody ... does not wait for your OK' sentence, but no true waste.

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 mutation tool with 11 params, no output schema, and full schema coverage, the description covers the key behavioral concerns an agent needs: partial semantics, reversibility, downstream impact on invoices, and auth. Little is missing.

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 all 11 parameters. The description only adds meaning for the 'inactive' flag ('retire a relation'); the rest of the parameters are left to the schema. Baseline 3 is appropriate when the schema does the heavy lifting.

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 ('Change fields of a relation') plus the alternate action ('set it inactive'). An agent can tell this is an update operation distinct from create_relation/get_relation/list_relations, though no sibling is named explicitly.

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 describing partial-update semantics and the inactive flag, but there is no explicit when-to-use guidance or routing against alternatives like get_relation (read first) or create_relation. Adequate but leaves selection to inference.

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