Anthropic API Error invalid_request_error: Prompt is too long

Error✕ Not retryable · fix the payloadHTTP 400 Bad RequestAI Provider

TL;DR · 10-second read

The prompt plus requested output exceeds the model’s context window. Trim history, summarize old turns or retrieve only the relevant chunks; retrying the same request always fails.

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What you see · exact log / response

anthropic.BadRequestError: Error code: 400 - {"type": "error", "error": {"type": "invalid_request_error", "message": "prompt is too long: 215337 tokens > 200000 maximum"}}

Fix

Being written

Copy-paste fixes for invalid_request_error are in the enrichment queue

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Last verified 2026-10-22 · Source: Anthropic API error reference + SDK docs · Official docs ↗ · ~4,400 searches/mo