Bfl API

What it does

When your agent uses it

• Tasks that involve Third-party API integration
• Tasks that involve Webhooks
• Tasks that involve Rate limiting

Example prompts

• “/bfl-api”

Requirements

• Python 3
• Node.js
• A Bash shell
• A credential in BFL_API_KEY
• A credential in YOUR_API_KEY

Workflow steps

4 steps, taken from the step headings in SKILL.md.

1. 1Submit Generation Request
2. 2Poll for Result
3. 3Download Image
4. 4Multi-Reference Example

What it can do on your machine

Read from SKILL.md and the folder at commit 8907d51. It shows what the files ask for, not the result of running them.

• Tool permissions

  Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.

  From allowed-tools in the SKILL.md frontmatter.

• Runs code

  Ships script files (Shell, Python and TypeScript), which the agent can run.

  Shell commands in SKILL.md call:

  • curl

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  Hosts in commands or code, which the agent is likely to contact:

  • api.bfl.ai
  • api.eu.bfl.ai
  • api.us.bfl.ai

  Also links to:

  • bfl.ai
  • dashboard.bfl.ai

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names these keys or tokens, usually read from environment variables:

  • BFL_API_KEY

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Bfl API loads about 2.5k tokens when it runs, and up to ~20k if it reads all its reference files. Until then it costs about 47 tokens; SKILL.md has 694 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~47

When it runs · the whole SKILL.md, loaded when a task matches

~2.5k

With references · SKILL.md plus every file in references/, read only if the agent opens them

~20k

Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.

Safety

• NoteMentions a .env fileSKILL.md:161

  2. **Save to `.env`** (recommended for persistence):

• NoteMentions a .env fileSKILL.md:163

  echo 'BFL_API_KEY=bfl_your_key_here' >> .env

• NoteMentions a .env fileSKILL.md:164

  echo '.env' >> .gitignore  # Don't commit secrets

Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.

SKILL.md

The full file from black-forest-labs/skills at commit 8907d51, republished under its MIT licence (© black-forest-labs). 694 words, ~2,492 tokens.

name

bfl-api

description

BFL FLUX API integration guide covering endpoints, async polling patterns, rate limiting, error handling, webhooks, and regional endpoints with Python and TypeScript code examples.

metadata.author

Black Forest Labs

metadata.version

1.0.0

metadata.tags

flux, bfl, api, integration, webhooks, rate-limiting

echo $BFL_API_KEY

curl -X POST "https://api.bfl.ai/v1/flux-2-pro" \
  -H "x-key: $BFL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "Change the background to a sunset",
    "input_image": "https://example.com/photo.jpg"
  }'

curl -X POST "https://api.bfl.ai/v1/flux-2-pro" \
  -H "x-key: $BFL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "The person from image 1 in the environment from image 2",
    "input_image": "https://example.com/person.jpg",
    "input_image_2": "https://example.com/background.jpg"
  }'

echo $BFL_API_KEY

x-key: YOUR_API_KEY

1. POST request to model endpoint
   └─> Response: { "polling_url": "..." }

2. GET polling_url (repeat until complete)
   └─> Response: { "status": "Pending" | "Ready" | "Error", ... }

3. When Ready, download result URL
   └─> URL expires in 10 minutes - download immediately

curl -s -X POST "https://api.bfl.ai/v1/flux-2-pro" \
  -H "x-key: $BFL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"prompt": "A serene mountain landscape at sunset", "width": 1024, "height": 1024}'

{ "id": "abc123", "polling_url": "https://api.bfl.ai/v1/get_result?id=abc123" }

curl -s "POLLING_URL" -H "x-key: $BFL_API_KEY"

{ "status": "Ready", "result": { "sample": "https://...", "seed": 1234 } }

curl -s -o output.png "IMAGE_URL"

curl -s -X POST "https://api.bfl.ai/v1/flux-2-pro" \
  -H "x-key: $BFL_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "prompt": "The cat from image 1 sitting in the cozy room from image 2",
    "input_image": "https://example.com/cat.jpg",
    "input_image_2": "https://example.com/room.jpg",
    "width": 1024,
    "height": 1024
  }'

© black-forest-labs, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 10 other files (references) in skills/bfl-api of black-forest-labs/skills.

• SKILL.md
• metadata.json
• references/api-key-setup.md
• references/code-examples/curl-examples.sh
• references/code-examples/python-client.py
• references/code-examples/typescript-client.ts
• references/endpoints.md
• references/error-handling.md
• references/polling-patterns.md
• references/rate-limiting.md
• references/webhook-integration.md

Open the folder on GitHubat commit 8907d51

Used in 1 other repository

We found 2 copies of this SKILL.md (exact, near-identical or edited) in other folders, from 1 other GitHub owner. This page covers the copy in black-forest-labs/skills, which our catalogue first saw on October 7, 2026.

• calesthio/OpenMontage.agents/skills/bfl-api.claude/skills/bfl-api