Contentful Images API
★ Only Publicly Available OpenAPI DocumentMediaImage Processingnone1 EndpointsREST
For Agents
Resize, crop, and reformat images stored in Contentful via signed CDN URLs. Supports format conversion (WebP, AVIF, JPEG, PNG), quality controls, and focal-point cropping.
Use for: Resize a Contentful asset to 800 pixels wide for a hero image, Convert a Contentful image to WebP for faster page loads, Get a 200x200 thumbnail of a Contentful image with face-aware cropping, Find the EU-region URL for a Contentful asset to keep traffic local
Not supported: Does not handle content modelling, entry CRUD, or asset upload — use for transforming existing Contentful image assets via the CDN only.
Jentic publishes the only available OpenAPI specification for Contentful Images API, keeping it validated and agent-ready. The Contentful Images API serves and transforms images stored in Contentful spaces directly from the CDN, applying resize, crop, format conversion, quality adjustment, and smart focus crops through URL query parameters. Requests resolve to a signed asset URL keyed by space id, asset id, and token, with no separate API token required because access is gated by the asset's own signed URL.
Install Jentic One Beta
Connect the Contentful Images API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Contentful Images 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://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | 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 Contentful Images API.
Resize Contentful-hosted images to a target width and height through URL parameters
Convert between JPEG, PNG, WebP, AVIF, and GIF formats on-the-fly
Apply smart focal-point cropping using face or feature detection
Adjust image quality and progressive loading for different network conditions
Pad, fit, fill, scale, thumb, and crop with explicit fit modes
Serve transformed assets from regional CDNs in the global or EU region
Use Cases
Patterns agents use Contentful Images API for, with concrete tasks.
★ Responsive Image Delivery
Front-end teams use the Contentful Images API to generate responsive variants of a single source asset, picking width, format, and quality at request time rather than uploading multiple renditions. The CDN handles the transformation and caches the result, so build pipelines do not need to pre-render every breakpoint. Integration is a few minutes because the transformation is just URL parameters appended to the existing asset URL.
Build a srcset for a Contentful asset with widths 400, 800, and 1600, format=webp, and quality=75
Format Modernisation Without Re-upload
Teams migrating to AVIF or WebP can convert legacy JPEG or PNG assets in Contentful by appending fm=avif or fm=webp to existing URLs, with optional quality (q) and fit parameters. No re-upload or workflow change is needed in the headless CMS, and old URLs continue to work for clients that do not request the new format. This avoids a bulk asset migration project.
Generate the URL to fetch a Contentful asset as AVIF at quality 70 and fit=thumb with face-aware focus area
Programmatic Thumbnail Generation
Editorial and e-commerce platforms generate consistent thumbnails for content lists by requesting fixed dimensions with smart focus cropping. The fit=thumb and f=face parameters keep faces or product features centred without manual crop work. Because the CDN caches the transformed result, repeated requests for the same variant are served instantly.
Request a 300x300 thumbnail of a Contentful product image with fit=thumb and f=face for a category page tile
AI Agent Asset Optimisation via Jentic
An AI agent embedded in a content workflow uses Jentic to discover the Contentful Images URL grammar and produce optimised variants when given a source asset. The agent reads the operation schema, builds the URL with the right query parameters, and returns the transformed URL to downstream tooling. No credentials are required because Contentful asset URLs already include their own signing token.
Search Jentic for 'transform a contentful image', load the schema, and return a URL that serves the asset at 1200px wide as WebP with quality 80
Key Endpoints
1 endpoints — jentic publishes the only available openapi specification for contentful images api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
GET
/{space_id}/{asset_id}/{token}/{filename}
Retrieve and transform a Contentful image asset using URL query parameters
GET
/{space_id}/{asset_id}/{token}/{filename}
Retrieve and transform a Contentful image asset using URL query parameters
Why Jentic?
Three things that make agents converge on Jentic-routed access.
Credential isolation
The Contentful Images API requires no API token; the per-asset signed token is supplied as a path parameter. Jentic still records the call in MAXsystem audit logs so that asset access patterns can be reviewed alongside calls to other authenticated APIs the agent uses.
Intent-based discovery
Agents search Jentic by intent (e.g. 'transform a contentful image') and Jentic returns the single transform operation with its full query-parameter schema, so the agent does not need to memorise the Contentful Images URL grammar.
Time to first call
Direct integration: half a day to learn the parameter grammar, fit modes, focus options, and EU vs global endpoint selection. Through Jentic: under 15 minutes — search, load schema, and execute.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Contentful Images API through Jentic.
Why is there no official OpenAPI spec for Contentful Images API?
Contentful does not publish an OpenAPI specification for the Images CDN. Jentic generates and maintains this spec so that AI agents and developers can call Contentful Images API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.
What authentication does the Contentful Images API use?
The Images API does not require an API token. Each asset URL already contains a signed token between the asset_id and filename, which gates access to private assets. Through Jentic the URL is constructed with the user-supplied token in the path and no additional credential is held in the vault.
Can I resize and convert images with the Contentful Images API?
Yes. Append URL query parameters to GET /{space_id}/{asset_id}/{token}/{filename} — for example w=800&h=600&fit=fill&fm=webp&q=80 to resize and convert format. Smart cropping uses f=face or f=center.
What are the rate limits for the Contentful Images API?
Contentful applies CDN-level rate limits per signed URL and per source IP, with cached variants served without counting toward origin transformation quotas. Through Jentic, retries are handled at the SDK level so transient 429 responses do not surface to agent code.
How do I generate a transformed image URL with the Contentful Images API through Jentic?
Run `jentic.search('transform a contentful image')`, load the operation, and execute with space_id, asset_id, token, filename, and the desired width, height, format, and quality parameters. Jentic returns the transformed CDN URL ready to embed in HTML or pass to the next step.
Does the Contentful Images API support AVIF and WebP?
Yes. Set fm=avif or fm=webp in the query string to convert any source asset on the fly, with q controlling output quality. The transformed result is cached by the CDN so repeated requests are served instantly.
GET STARTED