HTTP 400 on all OpenRouter models - curl works fine

[DonghunHa]

OpenRouter API key works with curl but hermes returns HTTP 400 for all models (claude-sonnet-4.6, nemotron-free, etc).
Version 0.8.0, WSL2 Ubuntu.
hermes doctor shows: OpenRouter API (HTTP 400).
curl test with same key returns valid response.
Fresh install today.

[ajsongpilot]

Same issue for me. OpenCode Zen also.

[enving]

I get at every model from openrouter similar error: API call failed (attempt 1/3): NotFoundError [HTTP 404]
🔌 Provider: openrouter Model: nousresearch/hermes-3-llama-3.1-405b:free
🌐 Endpoint: https://openrouter.ai/api/v1
📝 Error: HTTP 404: No endpoints found that support tool use. Try disabling "browser_back". To learn more about provider routing, visit: https://openrouter.ai/docs/guides/routing/provider-selection
📋 Details: {'message': 'No endpoints found that support tool use. Try disabling "browser_back". To learn more about provider routing, visit: https://openrouter.ai/docs/guides/routing/provider-selection', 'code': 404}
💡 No OpenRouter providers for nousresearch/hermes-3-llama-3.1-405b:free support tool calling with your current settings.
Check which providers support tools: https://openrouter.ai/models/nousresearch/hermes-3-llama-3.1-405b:free
⚠️ Non-retryable error (HTTP 404) — trying fallback...
❌ Non-retryable error (HTTP 404): HTTP 404: No endpoints found that support tool use. Try disabling "browser_back". To learn more about provider routing, visit: https://openrouter.ai/docs/guides/routing/provider-selection
❌ Non-retryable client error (HTTP 404). Aborting.
🔌 Provider: openrouter Model: nousresearch/hermes-3-llama-3.1-405b:free
🌐 Endpoint: https://openrouter.ai/api/v1
💡 This type of error won't be fixed by retrying.
─ ⚕ Hermes ─────────────────────────────────────────────────────────────────────────────────────────────────────────

Error: Error code: 404 - {'error': {'message': 'No endpoints found that support tool use. Try disabling
"browser_back". To learn more about provider routing, visit:
https://openrouter.ai/docs/guides/routing/provider-selection', 'code': 404}}

[dreamsmaner]

Solved:
Turned out I pasted my openrouter api key multiple times during setup because it didn't show any charactors and I thought I didn't paste it right.
Go edit .env file and reset the key and it worked.

===================================================================================

Same issue. New install on Android 9 Termux.

run hermes:

⚠️ API call failed (attempt 1/3): BadRequestError [HTTP 400]
🔌 Provider: openrouter Model: google/gemma-4-31b-it:free
🌐 Endpoint: https://openrouter.ai/api/v1
📝 Error: HTTP 400: Error code: 400
⚠️ Non-retryable error (HTTP 400) — trying fallback...
❌ Non-retryable error (HTTP 400): HTTP 400: Error code: 400
❌ Non-retryable client error (HTTP 400). Aborting.
🔌 Provider: openrouter Model: google/gemma-4-31b-it:free
🌐 Endpoint: https://openrouter.ai/api/v1
💡 This type of error won't be fixed by retrying.
─ ⚕ Hermes ───────────────────────────────────────────────────────────────────────

Error: Error code: 400
─────────────────────────────────────────────────────────────────────────────────

run hermes doctor:

◆ API Connectivity
✗ OpenRouter API (HTTP 400)

[GTP95]

I'm facing the same issue. I looked inside the .env file and there was no API key specified for OpenRouter. I put my key there and saved the file, but after restarting the gateway it still doesn't work and hermes chat -q "hello" --model anthropic/claude-sonnet-4.6 fails as well, here's the output:

   📝 Error: HTTP 400: Error code: 400
⚠ Non-retryable error (HTTP 400) — trying fallback...
❌ Non-retryable error (HTTP 400): HTTP 400: Error code: 400
❌ Non-retryable client error (HTTP 400). Aborting.
   🔌 Provider: openrouter  Model: anthropic/claude-sonnet-4.6
   🌐 Endpoint: https://openrouter.ai/api/v1
   💡 This type of error won't be fixed by retrying.

I still have credits on openRouter, so that isn't the problem. Any ideas on how to fix this?

[GTP95]

I was running it inside a Docker container. Deleting the container and reinstalling from scratch fixed it. But this doesn't tell what the root cause was.