[Bug] AxEquationExplorer and AxPlotToData fail with 429 OpenAI quota error

[dirkenglund]

Description

The AxEquationExplorer_find_functional_form and AxPlotToData_extract_numerical_series tools are failing with HTTP 500 errors due to backend OpenAI quota exceeded (429).

Environment

• MCP Server: axiomatic-mcp (installed via uvx)
• API Key: Configured correctly (verified)
• Date: 2026-01-25

Tools Affected

Tool	Status
AxDocumentParser	✅ Working
AxDocumentAnnotator	✅ Working
AxEquationExplorer	❌ 429 quota error
AxPlotToData	❌ 429 quota error

Error Message

Server error '500 Internal Server Error' for url 'https://api.axiomatic-ai.com/equations/derive/markdown'
Response: {"detail":"Could not compose expression: Error code: 429 - {'error': {'message': 'You exceeded your current quota, please check your plan and billing details.', 'type': 'insufficient_quota', 'param': None, 'code': 'insufficient_quota'}}"}

Similar error for plot extraction endpoint.

Analysis

The error indicates Axiomatic's backend OpenAI quota is exceeded - this is a server-side issue, not a user API key issue. The Document Parser and Annotator tools work fine, suggesting they use a different backend or don't rely on OpenAI.

Steps to Reproduce

1. Configure ax-mcp with valid API key
2. Call AxEquationExplorer_find_functional_form with any PDF
3. Observe 500 error with OpenAI 429 quota message

Expected Behavior

Tools should work when user has valid Axiomatic API key, regardless of Axiomatic's internal OpenAI usage.

Suggested Fix

• Check Axiomatic's OpenAI billing/quota
• Consider rate limiting or queuing for OpenAI-dependent endpoints
• Provide clearer error message distinguishing user quota vs backend quota issues

Feedback Submitted

Already submitted feedback via AxEquationExplorer_report_feedback and AxPlotToData_report_feedback MCP tools.