Short answer: there isn’t a way to turn off parameter validation in

run_deployment

in Prefect 3.x. The server enforces the deployment’s parameter schema, and

run_deployment

does not expose a

validate=False

style flag. What you can do instead (depending on what you’re trying to avoid validating): - Make your flow accept flexible parameters so the generated schema is permissive: - Use

**kwargs

(accept any keys), or - Use a single

params: dict

(accept a dict payload), or - Remove strict type annotations/defaults that make params required or strongly typed - After changing the flow signature, redeploy so the deployment’s parameter schema is regenerated. The schema is captured at deploy time. Example:

from prefect import flow
from prefect.deployments import run_deployment

@flow
def my_flow(**params):
    # params can contain any keys/values
    print(params)

# After modifying the signature, redeploy:
# my_flow.from_source("<https://github.com/owner/repo>", entrypoint="path/to/flow.py:my_flow").deploy(name="my-deployment")

run = run_deployment(
    name="my-project/my-flow/my-deployment",
    parameters={"any_key": 1, "another": "x"}  # now accepted by a permissive schema
)

Notes: - Even with a permissive schema, values must still be JSON-serializable. - Calling the REST API or client directly will not bypass validation if the deployment has a strict schema; you need to relax the flow signature and redeploy. If you can share: - your flow signature, - the exact validation error, and - whether you’re sending extra keys vs. “wrong type” values, I can suggest the smallest change to make your deployment accept what you need. Related docs: - Deployments and prefect.yaml - Server-side validation overview