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

The description discloses the critical WHOLESALE replace behavior — description is set to exactly what is passed and an empty/omitted value CLEARS it — which is a surprising semantic that annotations (openWorldHint: false, destructiveHint: false) do not convey. It also states the metadata-only boundary and that display_name is required and cannot be blank, adding real behavioral context beyond 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?

Two dense sentences with zero filler. The most important scoping fact (metadata only, not the JSON Schema body) is front-loaded, followed by the behavioral gotcha and the read-first workflow. Each clause earns its place and the structure mirrors the decision order an agent needs.

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 3-parameter update tool with a rich schema and output schema present, the description covers everything needed to call it correctly: what it updates, what it does not touch, what cannot be changed, the replace semantics, and the safe workflow. Sibling differentiation is explicit and no critical behavioral gap remains.

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% and the schema already documents each parameter, including 'Set wholesale — an empty value clears it', so the baseline is 3. The description adds operational meaning by tying parameters together — requiring both fields to preserve one unchanged and explaining the implication of the required display_name — going slightly beyond what the schema states.

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 states a specific verb and resource — 'Update a schema's display_name and description' — and immediately narrows scope with 'metadata only — this does NOT change the JSON Schema body'. It explicitly names the sibling that handles the excluded case (create_schema_version) and flags that the slug cannot be changed, so an agent can distinguish this tool from update-like siblings without opening 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?

The description gives explicit routing: use create_schema_version for JSON Schema body changes, use this tool for metadata only. It also provides a concrete operational procedure for the common case — 'read the current values with get_schema first and pass both' — and warns that the slug cannot be changed, which prevents attempts to use this tool for that purpose.

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