list_render_engines

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the useful context that the operation is a local detection of installed engines and includes the current assignment, but it does not disclose output ordering, detection limitations, or whether the list is dynamically refreshed.

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 English sentence is compact and front-loaded with the verb 'List'. The Chinese mirror adds bilingual accessibility, though it duplicates the same list of engine names, adding minor redundancy but no real bloat.

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 zero-parameter, read-only inventory tool, the description tells the agent what to expect: detected engine names and the currently assigned engine. It does not specify the exact return format, but with no output schema and minimal complexity, the description is adequate for correct invocation and basic result interpretation.

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?

The tool has zero parameters, so the baseline is 4. The description correctly contains no parameter-related information because there are no parameters to document. The empty schema and additionalProperties=false are sufficient.

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 uses the specific verb 'List' and names a precise resource: render engines detected on this machine, plus the currently assigned one. The enumerated engine names make the scope clear. It does not explicitly differentiate from sibling render_get_engine, but the plural 'engine list' plus current assignment disambiguates the tool's intent.

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 purpose itself implies when to use this tool: when an agent needs the set of detected render engines or the current renderer. However, the description does not explicitly mention alternatives or exclusions, such as pointing to render_get_engine for only the current engine or render_set_engine for changing it.

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