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

With destructiveHint=false and readOnlyHint=false already declaring this a non-destructive write, the description still adds critical behavioral facts: the write lands only in DRAFT and is invisible to shoppers until Publish, and unknown section types/setting keys are silently dropped. The drop behavior is a genuine hazard disclosure that no annotation conveys.

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?

Four tight sentences, front-loaded with the action and its draft-only scope, then prerequisites and the enabled:false trick. No filler; every clause carries operational weight.

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 mutation tool with no output schema, it covers draft semantics, silent-drop risk, section-hiding, and prerequisite reads. Minor gaps remain: no mention of return value, permission requirements, or whether the replacement is atomic, but nothing essential for calling it is missing.

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 only 67%, with `type`, `blocks`, `settings`, `enabled`, and `handle` undocumented in the schema. The description compensates for the important ones by explaining enabled:false (hide while keeping settings) and that unknown types/keys are dropped, though `handle` and `blocks` remain unexplained.

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?

Opens with a concrete verb+resource+scope: 'Replace a page's layout.' An agent immediately knows this is a whole-page layout write, distinct from sibling granular tools like define_section, set_theme_settings, or upsert_content.

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?

Gives ordered prerequisites clearly ('read list_section_types first', 'Call get_design_guide first if you have not'), which is real routing guidance. It does not name a when-not-to-use case or point at alternative page-editing tools for partial edits, so it falls short of an explicit 5.

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