List add-ons

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

Annotations already declare readOnlyHint=true, so safety is covered. 'Privileged context' hints at a permission requirement worth knowing but is left undefined, and nothing is said about return shape or ordering of results.

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?

A single tight sentence with the operation front-loaded and no filler. Every word earns its place.

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?

Adequate for a trivial zero-param read, and annotations cover safety. However, with no output schema, the description never indicates what a listed add-on looks like (name, id, enabled state), and 'privileged context' remains unexplained.

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?

Zero parameters, so baseline applies. The description adds the domain ('installed extensions') and context note, requiring nothing more from a no-arg tool.

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+resource: 'List installed extensions'. The 'privileged context' qualifier adds a meaningful nuance but the description doesn't differentiate from siblings like browser_extension_details or browser_tampermonkey_list, which also surface extension info.

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?

No guidance on when to use this versus browser_extension_details, browser_extension_permissions, or browser_tampermonkey_list, and no exclusions or prerequisites spelled out beyond the vague 'privileged context' phrasing.

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