browser_assert_element

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

No annotations exist, but description discloses behavior: returns state booleans, supports cross-iframe via backendNodeId, and polling with timeoutMs. It does not mention side effects, but the tool is read-only in nature.

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 short paragraphs front-load purpose, then usage, then additional features. Every sentence adds value with no redundancy.

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 state assertion tool with no output schema, the description lists all return fields. It covers parameters and usage guidance adequately, making it self-contained.

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%, but description adds meaningful context: explains timeoutMs for polling, backendNodeId for cross-iframe, and outcome fields. This goes beyond the bare schema.

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 clearly states the tool's purpose: 'Assert the state of a specific element without pulling the full semantic surface.' It lists return fields, distinguishing it from broader tools like get_semantic_surface or get_element_tree.

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?

Explicitly advises to use for 'quick state checks on known elements after an action, rather than re-fetching the entire page.' This provides clear when-to-use context and implies alternatives.

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