Get console errors

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

Annotations already declare readOnlyHint=true, so safety is covered. The description adds non-obvious behavior: the accumulation window resets at each navigate_url, and Chrome's duplicate 'Failed to load resource' messages are merged into the matching network entry — a deduplication detail an agent could not predict and that affects how it interprets result counts.

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 sentences, both front-loaded with the return contents first and the dedup caveat second. Every clause carries information; no filler or restatement of the tool name.

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-required-param read tool with annotations and a fully documented schema, the description covers what is collected, the time window, and dedup semantics. It stops short of describing the per-entry result shape (no output schema exists), which would help an agent parse results, but the core calling information is present.

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 100% and the single optional parameter firstPartyOnly is fully documented in the schema, so the baseline of 3 applies. The description adds nothing about the parameter, though nothing is missing that would cause misuse.

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 ('Return') and enumerates the exact resource contents: console errors, uncaught exceptions, failed network requests, HTTP >= 400 responses, and guard blocks. This clearly separates it from the sibling get_network_requests by scoping to errors only.

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 'recorded since the last navigate_url' implicitly tells the agent this must follow a navigation and resets per page load, which is useful usage context. However, it never explicitly says when to prefer this over get_network_requests or get_page_snapshot, leaving the agent to infer the boundary from the enumerated contents.

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