Screenshotline

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

With no annotations, the description carries the full burden, and it does disclose meaningful behavior: full rendering with JavaScript execution, lazy-image loading, and automatic consent-banner dismissal. It omits auth/rate-limit or failure behavior and never explicitly states it is a side-effect-free read, so it falls just short of full disclosure.

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 sentences, each earning its place: what it does, why the rendering matters, and when to prefer it over the sibling. The primary purpose and the capability differentiator are front-loaded.

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?

No output schema, so the description correctly states the return type (clean Markdown), and all six parameters are covered by the schema. It is nearly complete but says nothing about output size limits, pagination, or error cases for an unfetchable page.

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 the schema already documents all six parameters, setting the baseline at 3. The description reinforces the default-on cleanup behavior (consent banners) but adds no syntax, format, or default nuance beyond the schema itself.

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?

Specific verb+resource ("Render a web page") plus the output form ("clean Markdown"). It also differentiates from the sibling screenshot by describing the text-oriented use case, so an agent can pick between them without opening either schema.

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 names the alternative (screenshot) and the condition that selects this tool: "Prefer this over screenshot when you need to read or reason about the text." It also gives a context trigger for use — JS-heavy sites that return nothing to a plain HTTP fetch.

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

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

No annotations are provided, so the description carries the full behavioral burden, and it does disclose meaningful pipeline behavior: consent banners, ads, lazy-loaded images and late-rendering SPAs are handled. It stops short of noting latency implications of late-rendering SPAs or any failure/timeout behavior, so it falls just short of full disclosure.

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: the capability first, then the routing rule against the sibling. No redundancy and every clause carries information.

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 output schema, the description correctly states the return type ("return it as an image"), and the 11-parameter surface is fully covered by the schema. Minor gap: no note on whether auth or a reachable URL is required, though for a public-page capture tool this is a small omission.

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% across all 11 parameters (defaults, enums, and per-parameter meaning are already documented). The description adds no parameter-level detail beyond what the schema states, so the baseline of 3 is correct.

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 and resource ("Capture a screenshot of a web page") and immediately distinguishes itself from the sibling read_page by naming the visual-vs-text dimension. An agent can pick between the two without opening either schema.

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?

Explicit when-to-use rule ("when the layout, styling or visual appearance is what matters") paired with the named alternative and its selecting condition ("use read_page when you only need the text"). Nothing is left to inference.

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