validate_page

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

Annotations already declare readOnlyHint=true, consistent with a validator. The description adds genuine value beyond that by disclosing the severity model — which conditions block saving (duplicate/missing ids, missing types) versus which are only warnings (unknown types, form fields without field_name, dangling event targets).

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 tightly packed sentences, front-loaded with the action, then the return contract, then the sequencing rule. No filler.

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?

With no output schema, the description carries the return-value burden and mostly does: it names the error categories, warning categories, and the existence of 'stats'. It does not explain what stats contains or the exact error object shape, a minor residual gap for a validator.

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 there is only one optional parameter, so the baseline is 3. The description goes slightly further by showing the expected shape of 'source' as '{ sections: [...] }', which is not stated in the schema's 'object or JSON string' text.

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 ('Validate a page source') and immediately enumerates what it produces (blocking errors, warnings, stats), which also distinguishes it from mutation siblings like build_page and update_page_source.

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?

Explicit sequencing guidance: 'Always run this before build_page' tells the agent exactly when this tool belongs in a workflow. There is no stated when-not condition or named alternative validator, so it stops short of a 5.

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