How to Debug Why a Specific Channel Is Reported as Unavailable by the `doctor` Command

Run the doctor command with verbose output, inspect the raw result dictionary from check_all(), and isolate the channel's check method to identify configuration errors or backend exceptions.

The doctor command in the Agent-Reach repository provides a comprehensive health check for all configured channels. When a specific channel appears as unavailable, you need to trace the issue through the health-checker implementation in agent_reach/doctor.py and the individual channel's validation logic. This guide shows you how to debug channel unavailability by examining the source code, configuration files, and diagnostic outputs.

How the Doctor Command Works

The doctor command is a thin wrapper around the health-checker implementation defined in agent_reach/doctor.py. It iterates over every channel located in agent_reach/channels/ and invokes each channel's check method. The results are collected into a dictionary, then formatted into a Rich-styled report by the format_report function.

When a channel returns a status of warn, off, or error, the root cause typically resides within that channel's check implementation or its configuration dependencies. The check_all function (lines 12-35 in doctor.py) orchestrates this process by loading the user configuration and executing validation across all registered channels.

Step-by-Step Debugging Workflow

Run the Doctor Command with Verbose Output

Start by running the doctor command with verbose flags to capture detailed output:

python -m agent_reach.cli doctor --verbose

This displays the Rich-formatted report in your terminal. While this shows the final status, you need to access the raw data structures to debug specific failures.

Inspect the Raw Result Dictionary

To examine the exact values returned by the health check, invoke the check_all function directly from Python:

from agent_reach.doctor import check_all
from agent_reach.config import Config

cfg = Config()  # Loads ~/.agent-reach/config.yaml

results = check_all(cfg)  # Calls each channel's check method

# Inspect a specific channel (e.g., 'reddit')

print(results['reddit'])

The returned dictionary contains three critical fields:

• status: The health status (ok, warn, off, or error)
• message: A human-readable explanation of the issue
• active_backend: The selected backend (only present when healthy and multiple backends exist)

If the status is error, the message typically contains "体检异常：" followed by the exception details captured by the error handler in doctor.py.

Isolate the Channel's Check Method

Run the channel's validation logic in isolation to see full tracebacks. Locate the channel class (e.g., TwitterChannel in agent_reach/channels/twitter.py or RedditChannel in agent_reach/channels/reddit.py), then execute:

from agent_reach.channels.reddit import RedditChannel
from agent_reach.config import Config

cfg = Config()
reddit = RedditChannel()
status, message = reddit.check(cfg)
print(f"Status: {status}, Message: {message}")

If this call raises an exception, doctor.py catches it and reports status: "error". Running the check directly reveals the full stack trace, helping you identify whether the issue stems from network failures, authentication errors, or API rate limits.

Validate Configuration Dependencies

Channels in Agent-Reach are categorized into tiers based on configuration requirements:

• Tier 0: No configuration required
• Tier 1: Requires free API keys or login credentials
• Tier 2: Needs complex setup with multiple secrets

Verify that ~/.agent-reach/config.yaml contains the required credentials for tier 1 and 2 channels. Missing or malformed entries trigger warn or off statuses with messages like "MCP 已配置，但健康检查超时". The Config class in agent_reach/config.py handles loading this file, and you can inspect its contents:

from agent_reach.config import Config
cfg = Config()
print(f"Config path: {cfg.path}")
print(f"Loaded data: {cfg.data}")

Check Backend Selection Logic

Some channels support multiple backends (e.g., requests vs httpx). When healthy, the active_backend field indicates which implementation is active. According to the implementation in doctor.py (lines 24-27), this field is cleared when errors occur. If you see active_backend: None alongside status: "error", the channel threw an exception during initialization or connection.

Common Root Causes of Channel Unavailability

When debugging unavailable channels, investigate these frequent issues:

• Network failures: Many channels use requests and fail behind proxies or without proper user-agent headers
• Authentication errors: Platforms like XHS, Twitter, and Reddit require valid cookies or API tokens; expired credentials return warn status
• Rate limiting: Backend services may return specific error messages that the channel surfaces as warnings
• Configuration mismatches: Missing keys in ~/.agent-reach/config.yaml for tier 1/2 channels

Validate with the Test Suite

Confirm that the health-check logic functions correctly by running the comprehensive test suite in tests/test_doctor.py:

pytest tests/test_doctor.py -q

These tests validate the check_all orchestration and ensure that the doctor command handles both successful checks and exceptions according to the specification defined in the source code.

Summary

• The doctor command in Agent-Reach iterates through all channels in agent_reach/channels/ and calls their check method via check_all() in agent_reach/doctor.py
• Debug unavailable channels by inspecting the raw result dictionary from check_all() to view status, message, and active_backend fields
• Isolate the channel's check method in a Python REPL to reveal full exception tracebacks that the doctor command catches and summarizes
• Verify that ~/.agent-reach/config.yaml contains required credentials for tier 1 and 2 channels, checking with Config().data
• Use tests/test_doctor.py to validate that the health-check infrastructure works correctly

Frequently Asked Questions

Why does the doctor command show "error" status for a channel?

The error status indicates that the channel's check method raised an unhandled exception. The doctor.py file catches this exception and reports it with a message prefixed by "体检异常：". To see the full traceback and identify whether it's a network timeout, authentication failure, or code bug, run the channel's check method in isolation as shown in the debugging workflow above.

How do I find which configuration keys a channel requires?

Examine the channel's source file in agent_reach/channels/ (e.g., twitter.py or reddit.py). Tier 1 and 2 channels typically validate specific keys from the Config object within their check method. You can also inspect the Config class in agent_reach/config.py to understand how ~/.agent-reach/config.yaml is parsed, then verify that your configuration file contains the necessary API keys or session cookies.

What does "active_backend: None" indicate in the doctor output?

The active_backend field shows which implementation (such as requests or httpx) is currently in use for channels that support multiple backends. According to the logic in doctor.py lines 24-27, this field is cleared when a channel reports an error. Seeing active_backend: None alongside status: "error" confirms that the channel threw an exception before or during backend selection, rather than failing after successful initialization.

Can I run the doctor check on a single channel instead of all channels?

While the doctor command checks all channels by default, you can target a specific channel by importing its class directly from agent_reach.channels and calling its check method with a Config instance. This bypasses the check_all() loop in doctor.py and allows you to focus debugging on one channel at a time without waiting for unrelated health checks to complete.

{
  "mcpServers": {
    "instagit": {
      "command": "npx",
      "args": ["-y", "instagit@latest"]
    }
  }
}