BerriAI/litellm · error · ValueError

LINKUP_API_KEY is not set. Set `LINKUP_API_KEY` environment

Error message

LINKUP_API_KEY is not set. Set `LINKUP_API_KEY` environment variable.

What it means

The Linkup search provider (litellm/llms/linkup/search/transformation.py) requires a Bearer token on every request. resolve_server_api_key checks the caller-supplied api_key against the LINKUP_API_KEY environment variable (and related fallbacks); if neither yields a key, validate_environment raises ValueError before any HTTP call.

Source

Thrown at litellm/llms/linkup/search/transformation.py:70

    def validate_environment(
        self,
        headers: dict,
        api_key: str | None = None,
        api_base: str | None = None,
        **kwargs,
    ) -> dict:
        """
        Validate environment and return headers.
        """
        api_key = self.resolve_server_api_key(
            caller_api_key=api_key,
            caller_api_base=api_base,
            key_env_vars=("LINKUP_API_KEY",),
            base_env_var="LINKUP_API_BASE",
            default_api_base=self.LINKUP_API_BASE,
        )
        if not api_key:
            raise ValueError("LINKUP_API_KEY is not set. Set `LINKUP_API_KEY` environment variable.")
        headers["Authorization"] = f"Bearer {api_key}"
        headers["Content-Type"] = "application/json"
        return headers

    def get_complete_url(
        self,
        api_base: str | None,
        optional_params: dict,
        data: dict | list[dict] | None = None,
        **kwargs,
    ) -> str:
        """
        Get complete URL for Search endpoint.
        """
        api_base = api_base or get_secret_str("LINKUP_API_BASE") or self.LINKUP_API_BASE

        # Append "/search" to the api base if it's not already there
        if not api_base.endswith("/search"):

View on GitHub (pinned to 6c2dcb801b)

Solutions

export LINKUP_API_KEY="<your-key>" (from the Linkup dashboard) in the environment running LiteLLM
Or pass api_key explicitly on the call / in the proxy environment config
For LiteLLM proxy, store the key in the environment or secret manager keyed as LINKUP_API_KEY
Verify with printenv LINKUP_API_KEY in the exact process context

Example fix

# before
search_results = web_search(provider="linkup", query=q)

# after
import os
os.environ["LINKUP_API_KEY"] = "lk_..."
search_results = web_search(provider="linkup", query=q)

Defensive patterns

Strategy: validation

Validate before calling

import os

def ensure_linkup_key(api_key: str | None = None) -> str:
    key = api_key or os.getenv("LINKUP_API_KEY")
    if not key:
        raise ValueError("LINKUP_API_KEY missing: set it before calling Linkup search")
    return key

Try / catch

try:
    results = web_search(provider="linkup", query=q, api_key=ensure_linkup_key())
except ValueError as e:
    if "LINKUP_API_KEY" in str(e):
        raise RuntimeError("Deploy config incomplete: LINKUP_API_KEY not provisioned") from e

Prevention

Store LINKUP_API_KEY in the same secret manager/env pipeline as other provider keys
Add a config bootstrap check listing all required provider keys per enabled feature
If overriding LINKUP_API_BASE for a proxy, remember the key is still mandatory

When it happens

Trigger: Invoking Linkup web search (e.g. via litellm's search/tool-calling path with provider "linkup") without api_key and without LINKUP_API_KEY exported; key stored under a different variable name; env var missing in the deployed process.

Common situations: New Linkup integration where the key from the Linkup dashboard was never exported; key present locally but absent in Docker/CI; using api_base override (LINKUP_API_BASE) without also providing the key.

Related errors

AI-assisted analysis of BerriAI/litellm@6c2dcb801b (2026-08-15). Data as JSON: /api/errors/14d5d8466ddb7703. Report an issue: GitHub.