Report whether form autofill is available and enabled

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

Annotations already mark it read-only, and the description adds useful context about what is actually measured: the autofill module loading and exposing isAutofillEnabled. It also discloses the significant limitation that stored records are not writable through this build, though it does not describe the exact return shape.

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 core purpose is front-loaded in the first sentence, followed by measurement and scope caveats. It is reasonably concise, though the specific module paths are somewhat implementation-heavy for an agent-facing description.

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 status tool, the description covers purpose, measurement basis, and scope limitations. It does not fully specify the returned status fields, which matters slightly more because no output schema exists.

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 takes zero parameters, so parameter semantics are minimal. The baseline for a parameterless tool is 4, and there is no parameter-related misinformation.

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: report the address/credit-card autofill state. It clarifies this is status-only and explicitly rules out editing saved autofill entries, which helps separate it from data-manipulation siblings, though it does not name an alternative tool.

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 description gives a clear boundary: this tool only reports status, and editing saved autofill entries is out of scope because remote write is not exposed. It does not explicitly route the agent to a named sibling alternative, but the exclusion is clear.

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