Free discovery stub for the screenshot/PDF render lane. Same robots/SSRF guards as read_url. Currently returns a 503 (no charge) until Cloudflare Browser Rendering is provisioned on this account.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | absolute http(s) URL of a publicly reachable page |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description clearly states the tool currently returns a 503, has robots and SSRF guards similar to read_url, and is a free discovery stub. This sufficiently discloses the current behavior given the absence of annotations.
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 two sentences long, front-loads the purpose ('Free discovery stub'), and every sentence provides essential information without redundancy or excess.
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 simple tool with one parameter and no output schema or annotations, the description adequately covers purpose, current behavior, and limitations. It does not address future behavior but that is acceptable for a stub.
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 schema provides 100% coverage for the single parameter 'url' with a basic description. The description adds meaningful context about URL constraints (SSRF guards, robots.txt handling) and the tool's purpose, enriching semantics beyond the schema alone.
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 identifies the tool as a 'free discovery stub' for rendering screenshots/PDFs, giving a clear general purpose. However, it does not differentiate this stub from the actual render tools (render_pdf, render_screenshot) in terms of when one should be used over the other.
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 description implies use for testing the render pipeline without cost or triggering full rendering, but lacks explicit guidance on when to use this stub vs. the production render tools. No alternatives or exclusions are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Tools have distinct purposes (read full, read preview, render PDF, render preview, render screenshot). However, render_preview is a discovery stub for both PDF and screenshot, which could cause some ambiguity about which specific render tool it relates to.
Consistent verb_noun pattern with underscores: read_url, read_url_preview, render_pdf, render_preview, render_screenshot. Naming clearly indicates whether the tool reads text or renders visual output.
Five tools is appropriate for a web page reader that offers both text extraction and rendering capabilities. The set is neither too sparse nor overloaded.
The core read tools cover the primary purpose of fetching and converting URLs to markdown. The rendering tools are included but currently non-functional (return 503 or x402), leaving a gap in visual rendering capabilities. JavaScript-rendered pages are also unsupported.