Model Debugging

Model Debugging Skill

Use this skill when:

• Investigating model failures, high error rates, or service issues
• Finding users affected by errors (402 billing, 403 permissions, 500 backend)
• Analyzing Tinybird/Cloudflare logs for patterns
• Diagnosing specific request failures

Understanding Model Monitor Error Rates

Why does the Model Monitor show high error rates when models work fine manually?

The Model Monitor at https://monitor.pollinations.ai shows all real-world traffic, including:

• 401 errors: Anonymous users without API keys (most common)
• 402 errors: Users with insufficient pollen balance or exhausted API key budget
• 403 errors: Users denied access to specific models (API key restrictions)
• 400 errors: Invalid request parameters (e.g., openai-audio without modalities param)
• 429 errors: Rate-limited requests
• 500/504 errors: Actual backend failures (investigate these)

When you test manually with a valid secret key (sk_), you bypass auth/quota issues, so models appear to work fine.

Key insight: High 401/402/403/400 rates are expected from real-world usage. Focus investigation on 500/504 errors.

Data Flow Architecture

User Request → enter.pollinations.ai (Cloudflare Worker)
                    ↓
              Logs to Cloudflare Workers Observability
                    ↓
              Events stored in D1 database
                    ↓
              Batched to Tinybird (async, 100-500 events)
                    ↓
              Model Monitor queries Tinybird (model_health.pipe)

Structured Logging: enter.pollinations.ai uses LogTape with:

• requestId: Unique per request (passed to downstream via x-request-id header)
• status, body: Full error response from downstream services
• Context: method, routePath, userAgent, ipAddress

Quick Diagnostics

1. Check Model Monitor

View current model health at: https://monitor.pollinations.ai

2. Query Recent Errors from D1 Database

# Via enter.pollinations.ai worker (requires wrangler)
cd enter.pollinations.ai
npx wrangler d1 execute pollinations-db --remote --command "SELECT model_requested, response_status, error_message, COUNT(*) as count FROM event WHERE response_status >= 400 AND created_at > datetime('now', '-1 hour') GROUP BY model_requested, response_status, error_message ORDER BY count DESC LIMIT 20"

3. Capture Live Logs

enter.pollinations.ai (Cloudflare Worker)

cd enter.pollinations.ai
wrangler tail --format json | tee logs.jsonl
# Or with formatting:
wrangler tail --format json | npx tsx scripts/format-logs.ts

gen.pollinations.ai (image + text gateway)

Image and text generation now run inside the gen Cloudflare Worker (the legacy EC2 image-pollinations and text-pollinations services are decommissioned). Use wrangler tail from gen.pollinations.ai/:

cd gen.pollinations.ai
wrangler tail --format json | tee gen-logs.jsonl

Legacy anonymous image (OVH)

Anonymous traffic to image.pollinations.ai still terminates on the OVH host:

# Real-time logs
ssh -i ~/.ssh/id_rsa_ovh ubuntu@57.130.31.42 "sudo journalctl -u image-pollinations -f"

# Last 3 minutes
ssh -i ~/.ssh/id_rsa_ovh ubuntu@57.130.31.42 "sudo journalctl -u image-pollinations --since '3 minutes ago' --no-pager" > legacy-image-logs.txt

Common Error Patterns

Azure Content Safety DNS Failure

Error: getaddrinfo ENOTFOUND gptimagemain1-resource.cognitiveservices.azure.com Cause: Azure Content Safety resource deleted or misconfigured Impact: Fail-open (content proceeds without safety check) Fix: Create new Azure Content Safety resource and update .env:

AZURE_CONTENT_SAFETY_ENDPOINT=https://<new-resource>.cognitiveservices.azure.com/
AZURE_CONTENT_SAFETY_API_KEY=<new-key>

Azure Kontext Content Filter

Error: Content rejected due to sexual/hate/violence content detection Cause: Azure's content moderation blocking prompts/images Impact: 400 error returned to user Fix: User error - prompt violates content policy

Vertex AI Invalid Image

Error: Provided image is not valid Cause: User passing unsupported image URL (e.g., Google Drive links) Impact: 400 error returned to user Fix: User error - need direct image URL

Translation Service Down

Error: No active translate servers available Cause: Translation service unavailable Impact: Prompts not translated (non-fatal) Fix: Check translation service status

OpenAI Audio Invalid Voice

Error: Invalid value for audio.voice Cause: User requesting unsupported voice name Impact: 400 error returned to user Fix: User error - use supported voices: alloy, echo, fable, onyx, nova, shimmer, coral, verse, ballad, ash, sage, etc.

Oversized Text Seed Surfaced as 500

Error: 'seed' must be Integer, invalid request error, or a generic upstream 500 Cause: A client sent a seed above signed INT32 max (2147483647) to a strict provider Impact: The provider may misclassify invalid client input as 500, inflating model health errors Fix: Reject oversized seeds as 400 at gateway validation; group incidents by user, API key, and request shape before treating them as a model outage

Veo No Video Data

Error: No video data in response Cause: Vertex AI returned empty video response Impact: 500 error Fix: Check Vertex AI quota/status, may be transient

Environment Variables to Check

Image and text env vars now live in the gen Worker secrets (gen.pollinations.ai/secrets/{dev,staging,prod}.vars.json, SOPS-encrypted). Decrypt to inspect:

sops -d gen.pollinations.ai/secrets/prod.vars.json | jq 'keys[] | select(test("AZURE|GOOGLE|CLOUDFLARE|OPENAI"))'

Key variables:

• AZURE_CONTENT_SAFETY_ENDPOINT - Azure Content Safety API endpoint
• AZURE_CONTENT_SAFETY_API_KEY - Azure Content Safety API key
• GOOGLE_PROJECT_ID - Google Cloud project for Vertex AI
• AZURE_MYCELI_PROD_SWEDEN_API_KEY - Shared Azure API key (Kontext, GPT Image, GPT Image 1.5)

Updating Secrets

Secrets are stored encrypted with SOPS:

• gen.pollinations.ai/secrets/{dev,staging,prod}.vars.json
• enter.pollinations.ai/secrets/{dev,staging,prod}.vars.json

To update:

# Decrypt, edit, re-encrypt
sops gen.pollinations.ai/secrets/prod.vars.json

# Deploy to the gen Worker (secrets ship with the deploy)
cd gen.pollinations.ai && npm run deploy

Log Analysis Commands

# Count errors by type (against captured wrangler-tail JSON)
jq -r '.logs[]?.message[]? // .message? // empty' gen-logs.jsonl | grep -oE "(Azure Flux Kontext|Vertex AI|No active translate|getaddrinfo ENOTFOUND)" | sort | uniq -c | sort -rn

# Find content filter rejections
jq -r '.logs[]?.message[]? // .message? // empty' gen-logs.jsonl | grep -i "Content rejected" | sort | uniq -c

Model-Specific Debugging

Cloudflare Workers Observability API

The enter.pollinations.ai worker has structured logging enabled. You can query logs programmatically via the Cloudflare Workers Observability API.

Prerequisites

1. Get Account ID

# From wrangler.toml
grep account_id enter.pollinations.ai/wrangler.toml

2. Create API Token with Workers Observability Permission

Via Cloudflare Dashboard:

1. Go to https://dash.cloudflare.com/profile/api-tokens
2. Click Create Token
3. Click Create Custom Token
4. Configure:
   • Token name: Workers Observability Read
   • Permissions:
     • Account → Workers Scripts → Read
     • Account → Workers Observability → Edit (required for query API)
   • Account Resources: Include → Your Account
5. Click Continue to summary → Create Token
6. Copy the token immediately (shown only once)

3. Store Token Securely

The token is stored in SOPS-encrypted secrets:

• Location: enter.pollinations.ai/secrets/env.json
• Key: CLOUDFLARE_OBSERVABILITY_TOKEN

To add/update:

# Step 1: Decrypt to temp file
cd /path/to/pollinations
sops -d enter.pollinations.ai/secrets/env.json > /tmp/env.json

# Step 2: Add the token (use jq)
jq '. + {"CLOUDFLARE_OBSERVABILITY_TOKEN": "your_token"}' /tmp/env.json > /tmp/env_updated.json

# Step 3: Re-encrypt (must rename to match .sops.yaml pattern)
cp /tmp/env_updated.json /tmp/env.json
sops -e /tmp/env.json > enter.pollinations.ai/secrets/env.json

# Step 4: Cleanup
rm /tmp/env.json /tmp/env_updated.json

# Verify
sops -d enter.pollinations.ai/secrets/env.json | jq 'keys'

Note: The .sops.yaml config requires filenames matching env.json$ pattern.

API Endpoint

POST https://api.cloudflare.com/client/v4/accounts/{account_id}/workers/observability/telemetry/query

Query Examples

Setup: Get Credentials from SOPS

# Extract credentials from encrypted secrets
ACCOUNT_ID=$(sops -d enter.pollinations.ai/secrets/env.json | jq -r '.CLOUDFLARE_ACCOUNT_ID')
API_TOKEN=$(sops -d enter.pollinations.ai/secrets/env.json | jq -r '.CLOUDFLARE_OBSERVABILITY_TOKEN')

List Available Log Keys (Working)

This endpoint works and shows what fields are available:

curl -s "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/workers/observability/telemetry/keys" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"timeframe": {"from": '$(( $(date +%s) - 86400 ))'000, "to": '$(date +%s)'000}, "datasets": ["workers"]}' | jq '.result[:10]'

Query Recent Errors (Last 15 Minutes)

Note: The /query endpoint requires a saved queryId. For ad-hoc queries, use the Cloudflare Dashboard Query Builder or wrangler tail.

# This format requires a saved query ID

# Query errors with status >= 400
curl -s "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/workers/observability/telemetry/query" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "timeframe": {
      "from": '$(( $(date +%s) - 900 ))'000,
      "to": '$(date +%s)'000
    },
    "parameters": {
      "datasets": ["workers"],
      "filters": [
        {"key": "$workers.scriptName", "operation": "eq", "type": "string", "value": "enter-pollinations-ai"},
        {"key": "$metadata.statusCode", "operation": "gte", "type": "number", "value": 400}
      ],
      "calculations": [{"operator": "count"}],
      "groupBys": [
        {"type": "string", "value": "$metadata.statusCode"},
        {"type": "string", "value": "$metadata.error"}
      ],
      "limit": 50
    }
  }' | jq '.result.events.events[:20]'

Query Errors by Model

curl -s "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/workers/observability/telemetry/query" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "timeframe": {
      "from": '$(( $(date +%s) - 3600 ))'000,
      "to": '$(date +%s)'000
    },
    "parameters": {
      "datasets": ["workers"],
      "filters": [
        {"key": "$workers.scriptName", "operation": "eq", "type": "string", "value": "enter-pollinations-ai"},
        {"key": "$metadata.statusCode", "operation": "gte", "type": "number", "value": 400}
      ],
      "calculations": [{"operator": "count"}],
      "groupBys": [
        {"type": "string", "value": "model"},
        {"type": "string", "value": "$metadata.statusCode"}
      ],
      "limit": 100
    }
  }' | jq '.result.calculations[0].aggregates'

Get Raw Error Events with Full Details

curl -s "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/workers/observability/telemetry/query" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "timeframe": {
      "from": '$(( $(date +%s) - 900 ))'000,
      "to": '$(date +%s)'000
    },
    "parameters": {
      "datasets": ["workers"],
      "filters": [
        {"key": "$workers.scriptName", "operation": "eq", "type": "string", "value": "enter-pollinations-ai"},
        {"key": "$metadata.statusCode", "operation": "gte", "type": "number", "value": 500}
      ],
      "limit": 20
    }
  }' | jq '.result.events.events[] | {
    timestamp: .timestamp,
    statusCode: ."$metadata".statusCode,
    error: ."$metadata".error,
    message: ."$metadata".message,
    requestId: ."$workers".requestId,
    url: ."$metadata".url
  }'

List Available Log Keys

curl -s "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/workers/observability/telemetry/keys" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "timeframe": {
      "from": '$(( $(date +%s) - 3600 ))'000,
      "to": '$(date +%s)'000
    },
    "datasets": ["workers"],
    "filters": [
      {"key": "$workers.scriptName", "operation": "eq", "type": "string", "value": "enter-pollinations-ai"}
    ]
  }' | jq '.result.keys'

Structured Logging in enter.pollinations.ai

The worker uses LogTape for structured logging with these key fields:

• requestId: Unique ID per request (first 8 chars shown in logs)
• method: HTTP method (GET, POST)
• routePath: Request URL
• status: Response status code
• duration: Request duration in ms

Downstream errors are logged with:

log.warn("Chat completions error {status}: {body}", {
    status: response.status,
    body: responseText,
});

Tinybird Analytics (Alternative)

For aggregated model health stats, query Tinybird directly.

⚠️ Use the prod read token from SOPS — do NOT use .tinyb. The .tinyb in enter.pollinations.ai/observability/ points to the staging workspace (pollinations_enter_staging), which has ~no real traffic, so prod queries come back empty. Get the prod token instead:

TB=$(sops -d enter.pollinations.ai/secrets/prod.vars.json | jq -r '.TINYBIRD_READ_TOKEN')

This single token works for both pipes (/v0/pipes/...) and raw SQL (/v0/sql) against the prod workspace (pollinations_enter). The public Model Monitor reads cached health data through gen.pollinations.ai; it does not expose a Tinybird token.

H="https://api.europe-west2.gcp.tinybird.co"

# Get model health stats — pass minutes (default pipe window is short; use 240 for last 4h)
curl -s "$H/v0/pipes/model_health.json?token=$TB&minutes=240" | jq '.data'

# Detailed server-side error breakdown (full messages, upstream status/body, user attribution)
curl -s "$H/v0/pipes/recent_server_errors.json?token=$TB&minutes=240&limit=500" -o /tmp/errs.json

model_health columns (note: NOT error_count/error_rate): model, event_type, provider, model_used, total_requests, status_2xx, errors_4xx, errors_5xx, last_error_at, latency_p50_ms, latency_p95_ms, avg_latency_ms, last_request_at. Sort by errors_5xx to find backend issues.

recent_server_errors is the go-to pipe for root-causing (defined in enter.pollinations.ai/observability/endpoints/recent_server_errors.pipe, params minutes default 1440, limit default 200). It returns timestamp, status, upstream_status, upstream_host, upstream_body, message, error_code, error_class, model_requested, route_path, request_inputs, user_id, user_tier, api_key_id. There is no model_errors pipe.

JSON quirk: recent_server_errors rows contain raw newlines in stack/message, which break jq. Parse with Python instead: python3 -c "import json; d=json.load(open('/tmp/errs.json'),strict=False); ...".

Reading 5xx: upstream_status reveals the true cause. 502 (up 429) = provider throttle (e.g. Bedrock "Too many tokens" — account-level TPM quota, often a peak-traffic spike across many users, not one abuser). 502 (up 403) from api.openai.com with unsupported_country_region_territory = Cloudflare egress PoP in an OpenAI-blocked country. 500 (up 500) from Vertex/xAI = provider-side transient ("high load"/"Internal error") — no action.

Debugging Workflow

1. Check Model Monitor - https://monitor.pollinations.ai

   • Identify which models have high error rates
   • Note the error code breakdown (401, 402, 403, 400, 500, etc.)

2. Query Cloudflare Logs - Use the API queries above

   • Get raw error events with full details
   • Look for patterns in error messages
   • Group by user_id, api_key_id, route, and sanitized request_inputs before calling the pattern a model-wide outage
   • A concentrated burst from one caller can be invalid input even when the upstream reports 500

3. Correlate with Request ID - If you have a specific request ID:

   # Filter by request ID
   curl -s "https://api.cloudflare.com/client/v4/accounts/$ACCOUNT_ID/workers/observability/telemetry/query" \
     -H "Authorization: Bearer $API_TOKEN" \
     -H "Content-Type: application/json" \
     -d '{
       "timeframe": {"from": '$(( $(date +%s) - 86400 ))'000, "to": '$(date +%s)'000},
       "parameters": {
         "datasets": ["workers"],
         "filters": [
           {"key": "$workers.requestId", "operation": "eq", "type": "string", "value": "REQUEST_ID_HERE"}
         ],
         "limit": 100
       }
     }' | jq '.result.events.events'
   

4. Check Gateway Logs - Tail the gen Worker (image + text both run here):

   cd gen.pollinations.ai && wrangler tail --format json | tee gen-logs.jsonl
   

5. Test Model Directly - Verify if model is actually broken:

   TOKEN=$(grep ENTER_API_TOKEN_REMOTE enter.pollinations.ai/.testingtokens | cut -d= -f2)
   
   # Test text model
   curl -s 'https://gen.pollinations.ai/v1/chat/completions' \
     -H "Authorization: Bearer $TOKEN" \
     -H 'Content-Type: application/json' \
     -d '{"model": "MODEL_NAME", "messages": [{"role": "user", "content": "Test"}]}' \
     -w "\nHTTP: %{http_code}\n"
   
   # Test image model
   curl -s 'https://gen.pollinations.ai/image/test?model=MODEL_NAME&width=256&height=256' \
     -H "Authorization: Bearer $TOKEN" \
     -w "\nHTTP: %{http_code}\n" -o /dev/null
   

Current Status & Limitations

Cloudflare Observability API

What works:

• /telemetry/keys - List available log fields ✅
• /telemetry/values - Get unique values for a field ✅
• Token stored in SOPS: enter.pollinations.ai/secrets/env.json ✅

Limitations:

• /telemetry/query requires a saved queryId from the dashboard
• For ad-hoc queries, use Cloudflare Dashboard → Workers & Pages → pollinations-enter → Observability → Investigate
• Or use wrangler tail for real-time logs

Alternative: Tinybird (Recommended for Aggregates)

Tinybird provides pre-aggregated model health stats and raw event data.

Token Locations

• Prod read token (use this): enter.pollinations.ai/secrets/prod.vars.json → TINYBIRD_READ_TOKEN (via SOPS). Works for both pipes and raw /v0/sql against prod (pollinations_enter).
• .tinyb = staging workspace (pollinations_enter_staging) — empty of prod traffic. Only use for staging-specific debugging.

Basic Queries

# Prod read token from SOPS — works for pipes AND raw SQL
TB=$(sops -d enter.pollinations.ai/secrets/prod.vars.json | jq -r '.TINYBIRD_READ_TOKEN')

# Get model health (last 4h)
curl -s "https://api.europe-west2.gcp.tinybird.co/v0/pipes/model_health.json?token=$TB&minutes=240" | jq '.data'

Raw SQL Queries

The prod TINYBIRD_READ_TOKEN above can query the raw generation_event_v2 datasource directly via /v0/sql (verified). Reuse $TB:

# Find users with frequent 403 errors (last 24 hours)
curl -s "https://api.europe-west2.gcp.tinybird.co/v0/sql?token=$TB" \
  --data-urlencode "q=SELECT ge.user_id, any(users.github_username) AS github_username, argMax(ge.user_tier, ge.start_time) AS user_tier, count() as error_403_count
FROM generation_event_v2 ge
LEFT JOIN (SELECT id, github_username FROM d1_user WHERE synced_at = (SELECT max(synced_at) FROM d1_user)) users ON ge.user_id = users.id
WHERE ge.response_status = 403
  AND ge.start_time > now() - interval 24 hour
  AND ge.user_id != ''
  AND ge.user_id != 'undefined'
GROUP BY ge.user_id
ORDER BY error_403_count DESC
LIMIT 20"

# Find users with 500 errors (actual backend issues)
curl -s "https://api.europe-west2.gcp.tinybird.co/v0/sql?token=$TB" \
  --data-urlencode "q=SELECT ge.user_id, any(users.github_username) AS github_username, ge.model_requested, ge.error_message, count() as error_count
FROM generation_event_v2 ge
LEFT JOIN (SELECT id, github_username FROM d1_user WHERE synced_at = (SELECT max(synced_at) FROM d1_user)) users ON ge.user_id = users.id
WHERE ge.response_status >= 500
  AND ge.start_time > now() - interval 24 hour
GROUP BY ge.user_id, ge.model_requested, ge.error_message
ORDER BY error_count DESC
LIMIT 20"

# Check specific user's recent errors
curl -s "https://api.europe-west2.gcp.tinybird.co/v0/sql?token=$TB" \
  --data-urlencode "q=SELECT start_time, response_status, model_requested, error_message
FROM generation_event_v2
WHERE user_id = 'USER_ID_HERE'
  AND start_time > now() - interval 24 hour
ORDER BY start_time DESC
LIMIT 50"

Datasource Schema

The generation_event_v2 datasource is defined in enter.pollinations.ai/observability/datasources/generation_event_v2.datasource and includes:

• user_id, user_tier (join d1_user.id for the current GitHub display name)
• response_status, error_message, error_response_code
• model_requested, model_used
• total_price, total_cost
• start_time, end_time, response_time

Scripts

Helper scripts for common debugging tasks. Run from repo root.

Find Users with 403 Errors (Quota Issues)

# Find users with >10 403 errors in last 24 hours
.claude/skills/model-debugging/scripts/find-403-users.sh 24 10

Find 500 Errors (Backend Issues)

# Find 500+ errors grouped by user/model/message
.claude/skills/model-debugging/scripts/find-500-errors.sh 24

Check Specific User's Errors

# See a user's recent errors by internal user ID
.claude/skills/model-debugging/scripts/check-user-errors.sh USER_ID_HERE 24

Notes

• 401 errors: User authentication issues (no API key) - expected from anonymous traffic
• 402 errors: Pollen/billing issues (user ran out of credits or key budget) - expected
• 403 errors: Permission issues (model not allowed for API key) - expected
• 400 errors: Usually user input errors (bad prompts, invalid params) - expected
• 500 errors: Backend/infrastructure issues - investigate these
• 504 errors: Timeouts (model too slow or hung) - investigate these

Tested Models (All Working as of 2025-12-22)