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

Annotations only declare readOnlyHint=true and openWorldHint=false. The description goes beyond them by disclosing that props are validated before a link is produced, and that invalid props return an error naming the field to fix — genuinely useful failure-mode behavior. It stops short of describing link lifetime, rate limits, or whether validation is strict against the template spec.

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?

Three short sentences, front-loaded with the core action (validate + return link), followed by the user-facing outcome and the error contract. No filler and no repetition of schema content.

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 4-param read-only tool with no output schema, the description covers the action, the result artifact, and the failure behavior. The one gap is that the loosely typed nested props object is only characterized by reference to get_template_spec; an agent gets no hint about what 'invalid props' means structurally without reading the schema.

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 description coverage is 100%, so every parameter is already documented in the schema, including the source of props and searchId. The description adds only the framing 'filled-in props for a template', which is marginal value over the schema. Baseline 3 applies 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 compound verb (validate + return) on a clear resource (editor link / editable preview), and adds the downstream capability (MP4 export). It is easily distinguishable from render_preview and get_template_spec in practice, but it never names those siblings, so the differentiation is inferred rather than stated.

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 through flow references: props come from get_template_spec, searchId from search_templates, and the resulting link is where the user exports the MP4. However, there is no explicit when-to-use-this-vs-render_preview guidance or precondition (e.g. that the template must already have valid props), leaving the selection logic to inference.

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