api_screenshotReal browser screenshot of any page as PNG (base64), JS rendered. ?url=&width=1280&height=800&full=0|1 [HTTP x402 price: $0.02]
| Name | Required | Description | Default |
|---|---|---|---|
| params | No |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
Input schema / properties / params / additionalPropertiesRemoved value: -trueInput schema / properties / params / propertiesAdded value: +{
+ "height": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "default": null
+ },
+ "url": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "default": null
+ },
+ "width": {
+ "anyOf": [
+ {
+ "type": "string"
+ },
+ {
+ "type": "null"
+ }
+ ],
+ "default": null
+ }
+}Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the behavioral burden. It usefully discloses output encoding (PNG base64), JavaScript rendering, a full-page flag, and a monetary cost, but it omits auth requirements, failure modes, rate limits, and the meaning of the HTTP x402 payment mechanism.
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 whole definition is one compact sentence with no filler, front-loading the core behavior before parameter and pricing details. It could be clearer about parameter semantics, but it is appropriately concise.
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 screenshot tool, the description gives enough to attempt a call, including output format and price. Gaps remain: the full parameter is missing from the schema, there is no auth/error information, and no routing guidance among screenshot-like siblings.
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 itself has no descriptions, so the query-style template adds meaning and example values for url, width, and height. However, the template includes 'full=0|1', which is absent from the input schema, and it does not explain requiredness, value semantics, or valid ranges.
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 names a specific operation and resource: a real-browser screenshot of a page returned as PNG/base64 with JavaScript rendered. This clearly differentiates it from sibling text/PDF/meta tools like api_scrape, api_pdf, and api_og_image.
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?
Usage context is implied by 'Real browser screenshot ... JS rendered' and the URL-style parameters, but no explicit when-to-use or when-not-to-use guidance is given relative to sibling tools. There are no stated exclusions or alternatives.
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.