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

With no annotations, the description carries full burden. It discloses the exact JavaScript executed (document.documentElement.outerHTML or querySelector), the 100,000-character cap with truncation notice, and pageId auto-pick fallback. It does not explicitly state that it is read-only/side-effect-free, but 'Get' and the implementation imply a safe read operation.

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 well-structured sentences: purpose, implementation/selector, output cap and pageId fallback. No filler, front-loaded with the primary action, and every sentence adds relevant information.

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?

Despite no output schema, the description conveys what is returned (outerHTML), the optional selector behavior, truncation, and pageId fallback. It lacks explicit error handling or authentication requirements, but for a simple read-only DOM retrieval tool, it is sufficiently complete.

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 covers all 4 parameters with highly detailed descriptions, including pageId targeting and selector null behavior, so the description adds limited value beyond the schema. It does repeat/expand slightly on pageId auto-pick and selector behavior, but the schema already does the heavy lifting, warranting the baseline 3 for full coverage.

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 a specific verb ('Get') and clearly identifies the resource: outer HTML of a Safari page, optionally for a CSS-selector-matched element, on an iOS device via the Web Inspector. It distinguishes from siblings like ios_safari_evaluate by stating it returns outerHTML rather than evaluating arbitrary JavaScript.

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?

It provides clear context for when to use it: fetching page/element HTML. It also gives usage guidance for the pageId parameter ('Omit pageId to auto-pick'). However, it does not explicitly name alternatives or exclusions, relying on implicit differentiation from sibling tools.

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