strale-fallback

When your agent's primary API fails, Strale picks up the call.

strale-fallback wraps any function in your agent pipeline. When the primary call fails (timeout, 429, 503, malformed response), it automatically finds a matching Strale capability and executes it — returning structured JSON with a quality score.

Install

pip install strale-fallback

Usage

import os
from strale_fallback import with_fallback

@with_fallback(
    task_description="validate IBAN number",
    strale_api_key=os.environ["STRALE_API_KEY"]
)
async def validate_iban(iban: str):
    # Your primary API call — if this fails, Strale takes over
    return await my_primary_api.validate_iban(iban)

result = await validate_iban("SE3550000000054910000003")
print(result.source)           # "primary" or "strale_fallback"
print(result.data)             # structured JSON either way
print(result.capability_used)  # e.g. "iban-validate" (if fallback used)

Sync functions work too:

@with_fallback(task_description="check company sanctions")
def check_sanctions(company_name: str):
    return requests.get(f"https://my-api.com/sanctions/{company_name}").json()

How it works

1. Your primary function is called normally
2. If it throws (any HTTP error, timeout, or exception), strale-fallback calls POST /v1/suggest with your taskDescription to find the best matching Strale capability
3. It executes that capability with your function's arguments as inputs
4. Returns a FallbackResult with source: "strale_fallback" so you know which path was taken

FallbackResult

Quality threshold

# Only use Strale as fallback if SQS quality score >= 80
@with_fallback(
    task_description="check company sanctions",
    min_sqs=80
)
async def check_sanctions(company: str): ...

Environment

Set STRALE_API_KEY — or pass it directly to the decorator. Get a free key with trial credits: https://strale.dev/signup

Free capabilities (no key needed)

iban-validate, email-validate, dns-lookup, json-repair, url-to-markdown — these work even without an API key.

Full capability catalog: https://strale.dev/capabilities

License

MIT