AltTextLab API

Name: AltTextLab API API
Brand: AltTextLab API
Availability: InStock

★ Only Publicly Available SpecAI/MLVisionapiKey1 EndpointsREST

For Agents

Generate AI alt text for an image through a single x-api-key endpoint with 130+ language support and e-commerce mode. Useful for agents adding accessibility-grade descriptions to web, e-commerce, and email images.

Quickstart

Get started with AltTextLab API in minutes using your preferred integration method.

# Add to your MCP client config (Claude Desktop, Cursor, Windsurf)
{
  "jentic": {
    "url": "https://api.jentic.com/mcp",
    "auth": "oauth"
  }
}

# Then ask your agent:
"generate alt text for a product image"

# → Jentic returns the GET /events tool with parameter schema, agent executes.

Capabilities

What an agent can do with AltTextLab API API.

Generate alt text for an image by URL via POST /alt-text/generate

Request alt text in any of 130+ supported languages on a per-call basis

Use e-commerce mode to generate product-aware descriptions for storefront imagery

Provide context hints to bias the description toward a specific audience or tone

GET STARTED

Start building with AltTextLab API API

Explore with Jentic

View OpenAPI Spec

Jentic publishes the only available OpenAPI specification for AltTextLab API, keeping it validated and agent-ready.

Jentic publishes the only available OpenAPI specification for AltTextLab API, keeping it validated and agent-ready. AltTextLab is an AI alt-text generation service that exposes a single POST /alt-text/generate endpoint, supporting more than 130 languages and an e-commerce-aware mode for product imagery. Teams use it to add alt text to images at upload, retrofit existing libraries, and translate alt text into multiple locales. Authentication is a single x-api-key header issued from the AltTextLab dashboard.

Use Cases

Patterns agents use AltTextLab API API for, with concrete tasks.

★ On-Upload Alt Text for E-Commerce Catalogues

E-commerce teams call POST /alt-text/generate on every product image upload, optionally enabling e-commerce mode so the description leans into product attributes rather than generic visual cues. The single-endpoint design makes the integration trivial: one HTTP client and one header.

POST /alt-text/generate with the product image URL, lang='en', and e-commerce mode enabled, then write the returned alt text into the storefront's image record.

Multi-Language Localisation

Multinational sites get alt text per locale by calling the endpoint once per language. AltTextLab supports more than 130 languages, so the same workflow that populates English alt text can produce localised descriptions for the same image without a separate translation tool.

Loop over the site's locale list and call POST /alt-text/generate for each language, storing each result on the image record under that locale's column.

Accessibility Backfill Project

Accessibility teams running a backfill on an existing image library iterate through the asset list and call /alt-text/generate per image. Because every call is independent, the workflow parallelises easily and resumes cleanly after interruptions; the single-endpoint surface keeps the worker code small.

Iterate over the image inventory and call POST /alt-text/generate for any image that has no alt attribute, writing the response back to the asset record.

AI Agent Image Captioner via Jentic

An AI agent built on Jentic can take 'caption this image for our blog post in English and Spanish' and resolve it to two POST /alt-text/generate calls with the x-api-key safely vaulted in MAXsystem. Jentic returns the schema directly so the agent doesn't need to know the request body shape in advance.

Search Jentic for 'generate alt text for an image', load the POST /alt-text/generate schema, and execute it twice with lang='en' and lang='es' for the same image URL.

Key Endpoints

1 endpoints — jentic publishes the only available openapi specification for alttextlab api, keeping it validated and agent-ready.

METHOD

PATH

DESCRIPTION

POST

/alt-text/generate

Generate alt text for an image, with optional language and e-commerce mode

POST

/alt-text/generate

Generate alt text for an image, with optional language and e-commerce mode

Why though Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

AltTextLab x-api-key values are stored encrypted in the Jentic vault (MAXsystem). Agents only see a runtime-injected header at execution and never hold the raw key.

Intent-based discovery

Agents search Jentic with intents like 'generate alt text for an image' and receive the POST /alt-text/generate operation schema directly, with the language and e-commerce-mode parameters surfaced.

Time to first call

Direct AltTextLab integration: a few hours to wire auth and per-locale loops. Through Jentic: under 30 minutes to search, load, and execute the first alt-text generation.

Related APIs

Alternatives and complements available in the Jentic catalogue.

Alternative

AltText.ai API

Multi-endpoint alt-text platform with bulk-create and page-scrape modes

Choose AltText.ai when the workflow needs explicit bulk and page-scrape modes rather than AltTextLab's single-endpoint design.

Alternative

OpenAI API

General-purpose vision model with full prompt control over caption style and length

Choose OpenAI when alt-text style needs heavy prompt customisation beyond the accessibility-focused output AltTextLab returns.

Alternative

DeepAI API

Lightweight image captioning and tagging with simple REST access

Choose DeepAI for ad-hoc captioning when language coverage and e-commerce mode are not required.

Complementary

Cloudinary Upload API

Image storage and CDN delivery for the assets being captioned

Use Cloudinary alongside AltTextLab to host the source images and serve them through a CDN while AltTextLab generates the descriptions.

FAQs

Specific to using AltTextLab API API through Jentic.

Why is there no official OpenAPI spec for AltTextLab API?

AltTextLab does not publish an OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call AltTextLab 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 AltTextLab API use?

AltTextLab uses an x-api-key header on every request. Through Jentic, the key stays encrypted in the MAXsystem vault and the header is injected at call time, so the raw key never enters agent prompts.

Can I generate alt text in multiple languages with the AltTextLab API?

Yes. AltTextLab supports more than 130 languages. Pass the desired language code on POST /alt-text/generate to get the description in that locale, and call the endpoint again for each additional language you need.

What are the rate limits for the AltTextLab API?

Specific limits are not documented in the spec. Treat the endpoint as account-throttled and add retry-with-backoff for 429 responses; for backfill jobs of more than a few thousand images, contact AltTextLab to size the workload against your plan.

How do I generate alt text for a product image through Jentic?

Run pip install jentic and search with 'generate alt text for an image'. Load the POST /alt-text/generate schema, pass the image URL with e-commerce mode enabled, and execute. Jentic injects the x-api-key header from the vault.

Does the AltTextLab API have an e-commerce mode?

Yes. AltTextLab exposes an e-commerce mode that biases the description toward product attributes — colour, shape, fit, and visible branding — which is useful for storefront imagery where generic 'a man stands in a room' style alt text is unhelpful.