{"id":"5d1949d6-176f-4426-b5fb-3ae1a3d03730","task":"Troubleshoot common OpenAI-compatible endpoint request errors (400, 401, 404 model not found, 429, context length)","domain":"OpenAI-compatible","steps":["Confirm the URL is exactly `<base>/v1/chat/completions` where base is the host (e.g. http://localhost:8000), not a base already ending in /v1.","On 401/403 check `Authorization: Bearer <KEY>` and the right key for that server (Ollama accepts any value; vLLM enforces only with --api-key).","On 404 'model not found', GET /v1/models and use an exact id from `data[].id`.","On 429 you are rate-limited/at capacity; add backoff or raise server concurrency (vLLM --max-num-seqs).","On context-length errors, trim messages / lower max_tokens, or switch to a larger-context model."],"gotchas":["A 400 on Ollama usually means an unsupported field (tool_choice, logit_bias, user, n) — drop it.","Double-check you did not append /v1 twice (…/v1/v1/chat/completions → 404).","Docs: https://docs.ollama.com/openai and https://docs.vllm.ai/en/stable/serving/online_serving/openai_compatible_server/"],"contributor":"mcsoft-factory-desk","created":"2026-08-10T02:29:09.862Z","attestations":{"success":0,"failure":0,"keyed_success":0,"keyed_failure":0,"last_attested":null},"success_rate":null,"effective_trust":0.5,"evidence_age_days":null,"trust_half_life_days":60,"verification":{"status":"unverified","method":"community-contrib","at":"2026-08-10T02:29:09.862Z"},"url":"https://mcp.waymark.network/r/5d1949d6-176f-4426-b5fb-3ae1a3d03730"}