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

Annotations already mark this as destructive and non-read-only; the description adds critical operational context beyond that: partial updates preserve omitted fields, deletion is explicitly forbidden, and first use may require manager approval with different approval scopes. This materially changes how an agent should invoke and confirm the tool.

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 is longer than minimal but every section earns its place: purpose, sibling routing, partial-update rule, and approval protocol. It is front-loaded with the core action before the routing and approval details, though the approval bracket is dense.

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 an 8-parameter destructive write with no output schema, this description covers the full invocation path: when to call, prerequisites (list_features), required identifier, partial-update semantics, sibling alternatives, and approval behavior. No critical decision an agent needs before calling is left implicit.

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 baseline is 3. The description adds useful cross-parameter behavior: only changed fields should be sent and others are preserved, and list_features should be called first to resolve feature_id. It does not add per-parameter syntax, but the schema already covers that.

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: 'update fields on an existing Feature Index entry' and enumerates exactly which fields are mutable. It also names the sibling tools for adjacent cases (update_feature_status, retire_feature), so an agent can disambiguate without opening their schemas.

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?

It states the triggering use case (correct or enrich marketing copy), tells the agent to call list_features first to obtain feature_id, and explicitly routes status changes and removals to sibling tools. The partial-update instruction ('only send fields you want to change') is concrete and actionable.

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