AgentFuel API

Use AgentFuel to call Replicate, Anthropic, and ElevenLabs APIs using a single crypto-funded key. Generate a free af_ key, create an invoice to get a unique...

Security Scan

The skill's requirements and instructions are consistent with a gateway/proxy for multiple AI APIs and only request a single AGENTFUEL_KEY, but the skill is instruction-only, from an unknown source, and has a few metadata and privacy caveats you should review before trusting it with sensitive data or funds.

Purpose & Capability

The name/description (a crypto-funded API gateway that proxies Replicate, Anthropic, and ElevenLabs) matches the runtime instructions: endpoints, invoice/transfer endpoints, and auth mechanisms are all directly related to that purpose. Requiring AGENTFUEL_KEY is expected.

Instruction Scope

SKILL.md only shows curl and web_fetch calls to the gateway and does not instruct reading unrelated files or environment variables. However it encourages use of query-param auth (https://.../endpoint?key=YOUR_AF_KEY) which can increase risk of accidental key leakage via logs/referer; prefer header Authorization where possible. No steps instruct exfiltration unrelated data, but the gateway will receive request payloads (prompts, audio, etc.) — this is intrinsic to a proxy.

Install Mechanism

Instruction-only skill with no install spec and no code files — nothing is written to disk by the skill itself. Low install risk.

Credentials

Only one env var (AGENTFUEL_KEY) is required, which is proportionate to a gateway API. Minor metadata inconsistency: registry lists 'Primary credential: none' despite AGENTFUEL_KEY being required (likely a bookkeeping omission).

Persistence & Privilege

always is false and the skill does not request persistent/privileged system presence. The skill allows autonomous invocation (disable-model-invocation: false) which is platform default; combined with the gateway nature this means an agent could autonomously make proxied requests — expected but worth awareness.

Assessment

This skill appears to do what it says: proxy AI API calls through an AgentFuel key. Before installing, verify you trust agentfuel.dev (no homepage provided here) because all request payloads (prompts, files, audio) and payment operations go through their service and could be logged. Prefer using Authorization headers instead of ?key= in URLs to reduce leakage via logs/referer. Confirm the AGENTFUEL_KEY has limited scope if possible, rotate it if compromised, and monitor credits and transfers. Consider avoiding this gateway for highly sensitive data or production secrets until you can verify the operator (check their website, privacy policy, and reviews). The metadata omission of a primary credential is minor but note the source is unknown—exercise caution.

AgentFuel is a crypto-funded API credit broker for AI agents. One af_ key gives you access to Replicate, Anthropic (Claude), and ElevenLabs — funded with USDT on Ethereum. No credit cards. No per-service accounts.

Base URL: https://agentfuel.dev/v1 Auth: Authorization: Bearer $AGENTFUEL_KEY header, OR ?key=$AGENTFUEL_KEY query param Pricing: 1,000 credits = $1 USD

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Check Balance

With header auth (curl/exec):

curl https://agentfuel.dev/v1/balance \
  -H "Authorization: Bearer $AGENTFUEL_KEY"

With query param (web_fetch — no custom headers needed):

web_fetch: https://agentfuel.dev/v1/balance?key=YOUR_AF_KEY

Returns: { "credits": 12500, "key": "af_..." }

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Get Credits (USDT Invoice)

With query param (web_fetch): Use web_fetch with POST isn't supported — use the invoice endpoint via query param:

web_fetch: https://agentfuel.dev/v1/invoice?key=YOUR_AF_KEY&amount_usd=10

With header auth (curl/exec):

curl -X POST https://agentfuel.dev/v1/invoice \
  -H "Authorization: Bearer $AGENTFUEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{"amount_usd": 10}'

Returns: { "invoice_id": 1, "address": "0x...", "amount_usd": 10, "expires_at": "..." }

Send exact USDT amount to the address (ERC-20, Ethereum). Credits applied after ~6 confirmations (~2 min).

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Transfer Credits Between Keys

curl -X POST https://agentfuel.dev/v1/transfer \
  -H "Authorization: Bearer $AGENTFUEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{"to": "af_recipient_key_here", "amount": 1000}'

Auth is the SENDER's key. Returns 402 if insufficient credits.

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Calling Anthropic (Claude)

curl -X POST https://agentfuel.dev/v1/anthropic/messages \
  -H "Authorization: Bearer $AGENTFUEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "claude-sonnet-4-6", "max_tokens": 1024, "messages": [{"role": "user", "content": "Hello"}]}'

Available models: claude-sonnet-4-6, claude-haiku-4-5-20251001, claude-opus-4-6

Calling Replicate

curl -X POST https://agentfuel.dev/v1/replicate/predictions \
  -H "Authorization: Bearer $AGENTFUEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "black-forest-labs/flux-schnell", "input": {"prompt": "..."}}'

Calling ElevenLabs

curl -X POST "https://agentfuel.dev/v1/elevenlabs/text-to-speech/VOICE_ID" \
  -H "Authorization: Bearer $AGENTFUEL_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text": "Hello", "model_id": "eleven_turbo_v2_5"}' \
  --output speech.mp3

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Error Codes

Code	Meaning	Action
401	Invalid key	Check af_ prefix, use header or ?key= param
402	Insufficient credits	Create invoice, deposit USDT
429	Rate limited	Wait 60s
502	Upstream error	Retry after 10s