Anthropic SDK fails to map 413 and 529 HTTP status codes to typed exceptions

What this error means

Anthropic SDK does not map HTTP 413 (payload too large) or 529 (overloaded) to typed exceptions on Bedrock/Vertex is a Anthropic API failure pattern reported for developers trying to fix anthropic sdk throwing generic errors for 413 and 529 http status codes instead of typed exceptions on bedrock/vertex backends. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub PR anthropics/anthropic-sdk-python#1544 (2026-05-14) maps 413/529 to typed exceptions on Bedrock and Vertex backends. Without this fix, developers get untyped HTTP errors instead of actionable OverloadedError or similar. Category: Anthropic API error handling → Anthropic API.

Common causes

• GitHub PR anthropics/anthropic-sdk-python#1544 (2026-05-14) maps 413/529 to typed exceptions on Bedrock and Vertex backends. Without this fix, developers get untyped HTTP errors instead of actionable OverloadedError or similar. Category: Anthropic API error handling → Anthropic API.

Quick fixes

1. Confirm the exact error signature matches Anthropic SDK does not map HTTP 413 (payload too large) or 529 (overloaded) to typed exceptions on Bedrock/Vertex.
2. Check the Anthropic API account, local tool state, and provider configuration involved in the failing workflow.
3. Reduce request pressure, check quota or plan limits, and retry with backoff instead of immediate repeated requests.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/anthropics/anthropic-sdk-python/pull/1544

Evidence note: GitHub PR anthropics/anthropic-sdk-python#1544 (2026-05-14) maps 413/529 to typed exceptions on Bedrock and Vertex backends. Without this fix, developers get untyped HTTP errors instead of actionable OverloadedError or similar. Category: Anthropic API error handling → Anthropic API.

Related errors

• Anthropic API

FAQ

What should I check first?

Start with the exact Anthropic SDK does not map HTTP 413 (payload too large) or 529 (overloaded) to typed exceptions on Bedrock/Vertex text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Anthropic API workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without Anthropic SDK does not map HTTP 413 (payload too large) or 529 (overloaded) to typed exceptions on Bedrock/Vertex.