What causes "{str(e)} Connection to {self.server_ip} failed." in Fosowl/agenticSeek?

Start/verify the local LLM server and confirm it listens on the host:port in self.server_ip (curl the endpoint).

Fosowl/agenticSeek · error · ConnectionError

{str(e)} Connection to {self.server_ip} failed.

Error message

{str(e)}
Connection to {self.server_ip} failed.

What it means

In respond(), a ConnectionError raised while calling the provider's llm(history, verbose) is re-raised with an appended '\nConnection to {self.server_ip} failed.' so the developer knows which endpoint was unreachable. It means the HTTP request to the LLM backend (local server or cloud endpoint) could not establish/receive a connection.

Source

Thrown at sources/llm_provider.py:88

        load_dotenv()
        url = os.getenv("DOCKER_INTERNAL_URL")
        if not url: # running on host
            return "http://localhost", False
        return url, True

    def respond(self, history, verbose=True):
        """
        Use the choosen provider to generate text.
        """
        llm = self.available_providers[self.provider_name]
        self.logger.info(f"Using provider: {self.provider_name} at {self.server_ip}")
        try:
            thought = llm(history, verbose)
        except KeyboardInterrupt:
            self.logger.warning("User interrupted the operation with Ctrl+C")
            return "Operation interrupted by user. REQUEST_EXIT"
        except ConnectionError as e:
            raise ConnectionError(f"{str(e)}\nConnection to {self.server_ip} failed.")
        except AttributeError as e:
            raise NotImplementedError(f"{str(e)}\nIs {self.provider_name} implemented ?")
        except ModuleNotFoundError as e:
            raise ModuleNotFoundError(
                f"{str(e)}\nA import related to provider {self.provider_name} was not found. Is it installed ?")
        except Exception as e:
            if "try again later" in str(e).lower():
                return f"{self.provider_name} server is overloaded. Please try again later."
            if "refused" in str(e):
                return f"Server {self.server_ip} seem offline. Unable to answer."
            raise Exception(f"Provider {self.provider_name} failed: {str(e)}") from e
        return thought

    def is_ip_online(self, address: str, timeout: int = 10) -> bool:
        """
        Check if an address is online by sending a ping request.
        """
        if not address:

View on GitHub (pinned to ae57a23577)

Solutions

Start/verify the local LLM server and confirm it listens on the host:port in self.server_ip (curl the endpoint).
Correct the server IP/port configuration (get_internal_url result) for your environment, especially inside Docker (use host.docker.internal or the service name).
Read the original str(e) above the appended message — it contains the underlying request failure (refused/timeout/DNS).
Retry with backoff if the server was temporarily restarting; verify with the same URL from the same network context as the app.

Example fix

// before
provider = LLMProvider("ollama")  # server_ip points at localhost:11434 but nothing is listening
result = provider.respond(history)  # ConnectionError: ... Connection to 127.0.0.1 failed.
// after (terminal)
$ ollama serve &            # start the backend
$ curl http://localhost:11434/api/tags  # verify reachable
then rerun provider.respond(history)

Defensive patterns

Strategy: retry

Validate before calling

import socket

def server_reachable(host_port) -> bool:
    host, port = host_port.rsplit(":", 1)
    try:
        with socket.create_connection((host, int(port)), timeout=3):
            return True
    except OSError:
        return False

assert server_reachable(provider.server_ip), f"LLM server {provider.server_ip} is down"

Try / catch

import time
for attempt in range(3):
    try:
        return provider.respond(history)
    except ConnectionError as e:
        if attempt == 2:
            raise
        time.sleep(2 ** attempt)

Prevention

Start the local LLM server (e.g. ollama serve) before launching the app; health-check it in a startup script.
In Docker, use host.docker.internal or the compose service name instead of localhost for self.server_ip.
Add exponential-backoff retries around respond() for transient connection drops.
Log provider.server_ip at startup and curl it once to confirm reachability in the same network context.

When it happens

Trigger: Calling sync_llm_request/respond while the local inference server (e.g. Ollama, LM Studio) is not running or listening on a different port than self.server_ip; wrong host/port in provider config; server crashed mid-session; network/firewall blocking the endpoint; container networking where in_docker host resolution fails (get_internal_url picked the wrong URL).

Common situations: Forgetting to start `ollama serve` before running the agent; using localhost inside Docker when the server runs on the host; the model server bound to 127.0.0.1 while accessed from another container; wrong port after a version update of the local server.

Understand the failure class

Background: ECONNREFUSED and "connection refused" / "could not connect to server" errors: what they mean and how to fix them — this error's family across 44 libraries.

Related errors

AI-assisted analysis of Fosowl/agenticSeek@ae57a23577 (2026-08-30). Data as JSON: /api/errors/b92fe34071e0ad3e. Report an issue: GitHub.