Canvasflare API
Agent-ready OpenAPI document · curated by JenticMediaImage ProcessingapiKey4 EndpointsREST
Know of an official OpenAPI document? Contribute it →
For Agents
Render HTML to images and capture URL screenshots through a single hosted endpoint, then retrieve or delete the resulting image by id. Useful for social cards, OG images, and dynamic email assets.
Use for: Render an OG image from an HTML template for a blog post, I want to capture a screenshot of a competitor's landing page, Generate a social share card from an HTML snippet, Retrieve a previously rendered image by its id
Not supported: Does not handle video rendering, design editing, or asset hosting beyond generated images - use for HTML-to-image rendering and URL screenshots only.
Jentic publishes the only available OpenAPI specification for Canvasflare API, keeping it validated and agent-ready. The Canvasflare API renders HTML and CSS into PNG or JPEG images and captures full-page or viewport screenshots from arbitrary URLs. It is built for programmatic image generation in social cards, email banners, and OG images, and it returns persistent image ids that can be retrieved or deleted later. Engineering teams use it to replace headless-browser-on-a-server setups with a single hosted endpoint.
Install Jentic One Beta
Connect the Canvasflare API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Canvasflare API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fcanvasflare.com%2Fcanvasflare" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fcanvasflare.com%2Fcanvasflare" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Canvasflare API.
Render arbitrary HTML and CSS into a PNG or JPEG image
Capture a full-page or viewport screenshot of any public URL
Retrieve a previously generated image by its id for download or further use
Delete a generated image when it is no longer needed to manage storage
Generate dynamic OG and social share images from templated HTML
Use Cases
Patterns agents use Canvasflare API for, with concrete tasks.
★ Dynamic OG Image Generation
Blog and SaaS sites generate per-page Open Graph images so each link preview reflects the post title and author. POST /render accepts the HTML template populated with the page's metadata and returns an image url and id, which the page references in its og:image tag. The render runs on demand or at publish time and replaces a homegrown headless-Chrome service.
POST /render with an HTML template populated with the post title, subtitle, and author, then store the returned image id with the post record.
URL Screenshot Service
Monitoring, archiving, and reporting tools call GET /screenshot to capture how a webpage looks at a moment in time. The endpoint takes a target URL and returns a screenshot image, replacing the operational burden of running and scaling a headless browser fleet. Suitable for change detection workflows and visual regression checks of public pages.
GET /screenshot?url=https://example.com and store the returned image binary alongside the timestamp.
Email Banner Personalisation
Lifecycle email systems render personalised banner images per recipient using their first name, account tier, or recent activity. POST /render with a templated HTML banner returns a hosted image URL the email platform can reference inline, so each send shows a unique image without baking creative into the email build.
POST /render with an HTML banner template per recipient and place the returned image URL into the email send payload.
AI Agent Visual Output
An agent producing weekly summary cards uses Canvasflare via Jentic to turn structured output into a shareable image. The agent searches for the render operation, loads the schema, and submits a populated HTML snippet - credentials stay in your Jentic One instance and the agent receives only the image URL.
Search Jentic for 'render HTML to an image', load the renderImage schema, and execute POST /render with the agent's generated HTML.
Key Endpoints
4 endpoints — jentic publishes the only available openapi specification for canvasflare api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
POST
/render
Render HTML to an image
GET
/screenshot
Take a screenshot of a URL
GET
/image/{id}
Retrieve a generated image by id
DELETE
/image/{id}
Delete a generated image by id
POST
/render
Render HTML to an image
GET
/screenshot
Take a screenshot of a URL
GET
/image/{id}
Retrieve a generated image by id
DELETE
/image/{id}
Delete a generated image by id
Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring the Canvasflare API by hand means appending its api_key to every query string and calling the render, screenshot, and image routes yourself. Through Jentic you install once, import Canvasflare from the API Directory, store the key once, and your agent calls it.
Permission scoping
Canvasflare puts the image id in the URL path (/image/{id}), so a rule can pin your agent to one image: it can read that image and nothing else. You choose the operations it may call, so rendering new images or deleting one is not included unless you add it.
Credential isolation
Your Canvasflare api_key is stored once, encrypted, by your own Jentic One instance and appended to the query string at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'render HTML to an image' or 'screenshot a URL', and Jentic returns the matching Canvasflare operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Canvasflare API through Jentic.
Why is there no official OpenAPI spec for Canvasflare API?
Canvasflare publishes documentation but not a machine-readable OpenAPI spec. Jentic generates and maintains this spec so that AI agents and developers can call Canvasflare API via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer.
What authentication does the Canvasflare API use?
Canvasflare uses an API key passed as the api_key query parameter on every request. Through Jentic the key is stored encrypted in the vault and appended at execution time, so it never enters the agent's prompt context.
Can I render HTML into an image with the Canvasflare API?
Yes. POST /render with the HTML payload and the response includes an image id and URL. The image is hosted and can be fetched via GET /image/{id} until it is deleted.
How do I capture a webpage screenshot through Jentic?
Search Jentic for 'screenshot a URL', load the screenshotUrl operation, and execute GET /screenshot with the target URL. Canvasflare returns the captured image.
What are the rate limits for the Canvasflare API?
The OpenAPI spec does not enumerate rate limits. Render and screenshot endpoints are CPU-heavy on the server, so design for sequential calls per workflow and back off on 429 responses; check your Canvasflare dashboard for plan-specific quotas.
Can I delete an image I no longer need?
Yes. DELETE /image/{id} removes the generated image from Canvasflare's storage. Use this for ephemeral assets like one-time email banners to keep storage tidy.
Can I limit what my agent is allowed to do with the Canvasflare API?
Yes. Because you run your own self-hosted Jentic One instance, your own rules decide which Canvasflare operations the agent may call, so you can grant only GET /image/{id} to fetch a rendered image while withholding POST /render, GET /screenshot, and DELETE /image/{id}. Since the image id sits in the URL path, a rule can pin the agent to a single image so it reads that one image and nothing else. Your api_key stays stored encrypted in your instance and is appended at execution time, never entering the agent's prompt or context.
GET STARTED