The Token That Didn't Work: Debugging CIDgravity API Authentication in a Distributed Storage Cluster

Introduction

In the complex world of distributed storage systems built on the Filecoin network, diagnosing why deals aren't flowing can feel like tracing a signal fault through miles of wiring. On February 4, 2026, a developer working on the Filecoin Gateway (FGW) project found themselves in exactly this position. The production QA cluster—three physical nodes running a horizontally scalable S3-compatible storage system backed by Filecoin—had stalled. Deals, the fundamental mechanism by which storage is committed on the Filecoin network, had simply stopped flowing. The cluster was healthy, the wallet had balance and datacap, groups were in the ready-for-deals state, but no new deals were being proposed. The culprit appeared to be a timeout from the CIDgravity API, the external service that provides on-chain deal state information. But as the developer would soon discover, the real problem was hiding in plain sight: a mismatched authentication header.

The Message: A Diagnostic Probe

The subject message, indexed at position 2253 in the conversation, is a single bash command executed by the AI assistant. It represents a critical diagnostic step in a longer debugging session. The command retrieves the CIDgravity API token from a remote node, then uses curl to test the get-on-chain-deals (GOCD) endpoint with an Authorization: Bearer header:

# Try the actual GOCD endpoint with the token
TOKEN=$(ssh 10.1.232.83 "sudo cat /home/fgw/.ribswallet/cidg.token")
echo "Token (first 10 chars): ${TOKEN:0:10}..."
echo ""
echo "=== Testing GOCD endpoint ==="
curl -v --max-time 30 -X POST "https://service.cidgravity.com/private/v1/get-on-chain-deals" \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $TOKEN" \
  -d '{"clientId": "f02097088"}' 2>&1 | tail -30

The output reveals the token (partially redacted) and the beginning of the HTTP response. The tail -30 truncation is significant—it cuts off before showing the HTTP status code, but the response headers visible in the output suggest the request completed. However, the next message in the conversation (index 2254) reveals the critical finding: the API returned 401 Unauthorized with the message "No API key found in request."

Why This Message Was Written: The Reasoning and Motivation

To understand why this specific command was necessary, we need to trace the chain of reasoning that led to it. The session began with a clear directive from the user: "First - look at logs and see why rbdeal deals are not flowing, then deploy." The developer had just committed and built a new version of the kuri binary that included HTTP-only repair workers and removed the legacy Lassie/Graphsync retrieval code. But before deploying this new binary, the user wanted to understand why the existing deployment had stalled.

The assistant's investigation revealed a clear pattern in the logs. The deal check loop was running every few minutes, but each iteration ended with the same error:

deal check loop failed {"error": "Post \"https://service.cidgravity.com/private/v1/get-on-chain-deals\": context deadline exceeded (Client.Timeout exceeded..."}

The CIDgravity API was timing out. But why? The assistant systematically worked through the possibilities:

  1. Network connectivity: A curl test from the kuri1 node showed the connection established successfully to 212.106.124.236:443. The network path was open.
  2. API token validity: The configuration showed CIDGRAVITY_API_TOKEN was loaded from a file at /home/fgw/.ribswallet/cidg.token. But was the token correct?
  3. API endpoint behavior: The assistant needed to replicate exactly what the kuri service was doing, but with more visibility. The subject message represents the third step in this diagnostic chain—directly testing the API endpoint with the actual token to see if authentication was the issue. The assistant's reasoning was sound: if the API was reachable but timing out, perhaps the token was invalid or the authentication mechanism was wrong. By testing with curl, the assistant could see the raw HTTP response and determine whether the API was rejecting the request before processing it.

How Decisions Were Made

Several decisions shaped this message, both explicit and implicit:

Decision 1: Test from the local machine rather than the kuri node. The assistant ran the curl command from the development workstation, not from the remote node. This was a practical choice—the assistant had direct shell access to the local machine and could capture the token via SSH. However, it introduced a subtle variable: network latency and routing from the local machine might differ from the kuri node. The assistant would later (in message 2261) re-run the test from the kuri node itself to confirm the API worked there too.

Decision 2: Use Authorization: Bearer as the authentication header. This was an assumption—and, as it turned out, an incorrect one. The assistant assumed that the CIDgravity API used the standard Bearer token authentication scheme. This is a reasonable default; many APIs use Authorization: Bearer <token>. But the CIDgravity API actually uses a custom header: X-API-KEY. The assistant didn't know this yet, and the error message "No API key found in request" was the clue that would lead to the correction.

Decision 3: Include clientId in the request body. The assistant used {"clientId": "f02097088"} as the POST body, matching the client ID shown in the wallet info. This was based on the assumption that the API required a client identifier. Later tests (message 2260) would use an empty body {} and still get a successful response, suggesting this parameter wasn't strictly necessary.

Decision 4: Truncate output with tail -30. This seemingly minor decision had a significant impact on the debugging process. By showing only the last 30 lines of verbose curl output, the assistant cut off the HTTP status line and response body. The next message in the conversation reveals that the response was a 401, but this isn't visible in the subject message itself. The truncation was likely intended to keep the output readable, but it meant the critical information wasn't displayed until the assistant followed up.

Assumptions Made

The message reveals several assumptions, some correct and some not:

Correct assumption: The token was stored in a file accessible via SSH. The assistant correctly assumed that sudo cat /home/fgw/.ribswallet/cidg.token would work on the remote node. This was validated by the output showing the token's first 10 characters.

Correct assumption: The API endpoint was HTTPS on port 443. The curl output confirms TLS handshake completion and certificate validation.

Incorrect assumption: The API used Bearer token authentication. This was the critical mistake. The CIDgravity API uses X-API-KEY as the authentication header, not Authorization: Bearer. This mismatch caused the 401 error that would be discovered in the follow-up message.

Incorrect assumption: The timeout was caused by the API being slow. The assistant initially believed the 30-second client timeout was being exceeded because the API was taking too long to respond. In reality, the API responded in ~2.6 seconds when called correctly. The timeout was likely caused by the authentication failure—the API may have been returning an error response that the client code didn't handle properly, or the connection was being reset after the auth failure.

Input Knowledge Required

To fully understand this message, several pieces of context are necessary:

  1. The architecture of the FGW system: The cluster consists of three physical nodes (10.1.232.82-84) running an S3 frontend proxy and two kuri storage nodes. The kuri nodes use the CIDgravity API to discover on-chain deals and manage storage proposals.
  2. The deal flow pipeline: The deal_tracker.go code runs a check loop that first calls runCidGravityDealCheckLoop to get on-chain deal states, then calls runSPDealCheckLoop and runDealCheckCleanupLoop to make new deals. If the CIDgravity call fails, the entire loop aborts and no new deals are made.
  3. The CIDgravity API: An external service that provides information about Filecoin storage deals. It requires authentication via an API token.
  4. The wallet configuration: The cluster uses wallet address f15nikeuukgjpk3rf3ndmxljgroagj52vdgznkcwy with client ID f02097088, and the API token is stored in a file at /home/fgw/.ribswallet/cidg.token.
  5. The previous debugging steps: Messages 2241-2252 established that the deal check loop was timing out, the API was reachable, the wallet had sufficient balance and datacap, and groups were in the ready-for-deals state.

Output Knowledge Created

This message produced several valuable pieces of information:

  1. The token format: The output reveals the token starts with f02097088- (the client ID followed by a hyphen and a longer secret). This confirms the token is a composite of client ID and secret key.
  2. The API is reachable from the local machine: The TLS handshake completed successfully, confirming the API endpoint is operational and accessible from the development network.
  3. The authentication mechanism needs investigation: The truncated output shows the beginning of the HTTP response but cuts off before the status code. However, the follow-up message reveals this was a 401 error, which is the critical finding.
  4. The Authorization: Bearer approach doesn't work: This negative result is valuable—it rules out one authentication mechanism and points toward the correct one (which the assistant would discover in message 2260 by examining the source code).

The Thinking Process Visible in the Reasoning

The assistant's reasoning process is visible in the sequence of commands leading up to this message. Looking at the conversation flow:

  1. Message 2241: The assistant checks deal-related logs and finds the CIDgravity timeout error. This establishes the symptom.
  2. Messages 2242-2243: The assistant tests basic connectivity to the CIDgravity API and confirms the network path is open. This rules out a network issue.
  3. Messages 2244-2247: The assistant checks group states, deal summaries, wallet info, and balance manager info. This establishes that the cluster is otherwise healthy and ready for deals.
  4. Messages 2248-2252: The assistant reads the deal tracker source code to understand the flow. This reveals that the CIDgravity check runs first and blocks the rest of the deal pipeline if it fails.
  5. Message 2253 (the subject): The assistant directly tests the API with the actual token to see if authentication is the issue. The thinking is methodical and follows a clear diagnostic pattern: observe the symptom, verify the infrastructure, check the configuration, trace the code path, and finally replicate the failing call manually. Each step narrows the possible causes. What's particularly interesting is the assumption about the authentication header. The assistant didn't immediately check the source code to see how the API call was constructed—that step came after the manual test failed. This is a natural debugging approach: try the most common authentication method first, and if it fails, check the code for the actual implementation. The follow-up messages (2254-2260) show exactly this pattern: after the 401 error, the assistant searches for the authentication header in the codebase, finds that it uses X-API-KEY, and re-tests successfully.

Mistakes and Incorrect Assumptions

The primary mistake in this message was the assumption about the authentication header. The assistant used Authorization: Bearer when the API expected X-API-KEY. This is a forgivable error—Bearer tokens are the industry standard for REST APIs, and many developers would make the same assumption. However, it did cost time: the assistant had to run additional commands to discover the correct header format.

A secondary issue is the output truncation. By using tail -30, the assistant cut off the HTTP status line and response body. The verbose curl output includes many lines of TLS handshake details before the HTTP response, so the status code ended up beyond the 30-line window. A better approach would have been to use -w "\nHTTP Status: %{http_code}\n" to explicitly print the status code, or to pipe through grep -E "^< HTTP/" to extract just the response headers.

Conclusion

Message 2253 represents a pivotal moment in a complex debugging session. It's the point where the developer moves from observing a symptom (API timeout) to actively probing the API to understand why. The negative result—a 401 Unauthorized—provides the crucial clue that leads to the correct authentication mechanism. Within minutes, the assistant would discover the X-API-KEY header in the source code, re-test successfully with a 2.6-second response time, and confirm that the API was working correctly.

The real lesson here is about the nature of distributed systems debugging. In a system spanning multiple physical nodes, external APIs, and complex authentication flows, the simplest explanation is often the right one. The API wasn't slow; it was rejecting unauthenticated requests. The timeout wasn't a performance issue; it was a consequence of the client code not handling the authentication failure gracefully. And the fix wasn't a configuration change or a code rewrite—it was understanding the correct header name.

This message also illustrates the value of replicating a failing call manually. By running the exact same API call that the kuri service makes, but with full visibility into the HTTP response, the assistant was able to see what the application code couldn't: the authentication failure. In distributed systems, where logs are often truncated and error messages are ambiguous, there's no substitute for getting your hands dirty with curl.