assert_url

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

With no annotations provided, the description carries the full behavioral disclosure burden. It clearly states that the assertion waits up to 7 seconds and raises an exception on mismatch, which is useful and non-obvious. It does not cover finer details like URL normalization or case sensitivity, but the core failure behavior is transparent.

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?

Two short, efficient sentences. The main purpose is stated first, and the timeout/exception behavior is added in the second sentence without any redundant wording.

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 one-parameter assertion tool, the description provides the key semantics: exact matching, a timeout, and failure behavior. The existence of an output schema reduces the need to describe return values. The main remaining gap is the precise URL format expected, but overall the tool is adequately described for correct use.

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 input schema provides no description for the required 'url' parameter, so the description must compensate. It clarifies that the parameter is the expected URL to compare against the current page URL, but it does not specify the expected format (e.g., fully qualified, with protocol, trailing slash handling). This is partial compensation for a single simple parameter.

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 states a specific action and resource: assert that the provided URL matches the current URL exactly. The word 'exactly' clearly distinguishes it from the sibling assert_url_contains, eliminating ambiguity about what is being verified.

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 'exactly' keyword implies this tool is for exact-match assertions and not for partial/substring matches, which would be handled by assert_url_contains. However, no explicit guidance is given about when to choose this over alternatives or when not to use it, leaving the usage to inference.

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