browser_read_pages

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

With no annotations, the description carries the full behavioral burden and does so well: each URL opens in a background tab of an existing window, the whole page is read, the tab is closed, and nothing is left open. It also discloses return format, link notation, per-page character limits, continuation behavior, partial-failure isolation, and the captcha caveat for search URLs.

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?

Despite being a dense paragraph, it is front-loaded with the core purpose and the primary alternative, and every sentence adds operational value. There is no filler or repetition.

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 no-annotation, no-output-schema tool with five fully described parameters, the description covers the return shape, size limits, continuation, tab lifecycle, partial failure, and search-engine caveat. An agent has enough information to call it correctly without opening the schema.

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%, so all five parameters are already documented in the schema. The description reinforces the 15,000-character limit and the read-on behavior tied to the `from` parameter, but adds little parameter-level syntax or nuance beyond what the schema already provides.

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 starts with a specific verb and resource: "Read web pages." It immediately distinguishes the tool from a built-in fetch tool and from browser_new_tab, which is for acting on pages, so an agent can tell exactly what this tool is for.

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?

It explicitly says to use this instead of WebFetch, explains why (returns page text rather than a summary), and says not to use it for search-results URLs because of captchas. It also routes acting-on-page use to browser_new_tab, covering both when to use and when not to use it.

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