network_failures

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It does convey that the operation is a read-only listing and defines the failure filter, but it omits important behavioral context such as per-tab scoping, whether DevTools attachment is required, and what the returned list contains beyond the status threshold.

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 description is a single, front-loaded sentence with zero filler. It states the tool's purpose and its main filtering condition as economically as possible.

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?

With no annotations and no output schema, the description needs to explain return shape, tab scoping, and any prerequisites. It only describes the core filter, leaving the required tabId unexplained and return format unspecified. This is not complete enough for confident invocation without relying on external knowledge.

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 description coverage is 0%, and the description does not explain either parameter. 'tabId' is required but its meaning and role are not mentioned, and 'failuresOnly' is only loosely implied by the word 'failed'. No additional parameter semantics are provided 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 uses a specific verb ('List') and a specific resource ('failed HTTP requests or responses') with an explicit threshold ('status >= 400'). This clearly distinguishes it from siblings like network_requests, which would presumably return all network entries.

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 phrase 'only failed' and the status threshold provide clear context for when this tool should be used: when the agent wants failures rather than the full network log. It does not explicitly name alternatives or state when not to use it, but the filter is unambiguous enough for most routing decisions.

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