762 pages for error.

Retrieve Message Batch results Claude Developer Platform · in the page api/messages/batches/results …uest. Contains a Message output if processing was successful, an error response if processing failed, or the reason why processing was not attempted, such as cancellation or expiration. - `M… Retrieve a Message Batch Claude Developer Platform · in the page api/messages/batches/retrieve …sing ends when every request in a Message Batch has either succeeded, errored, canceled, or expired. format: date-time - `expires_at: string` RFC 3339 datetime string representing the tim… Count tokens in a Message Claude Developer Platform · in the page api/messages/count_tokens …ing the field. - `oversized_image: optional "downsize" or "error"` What the server does when this image exceeds the model's maximum image size. `"downsize"` (the default) scale… Create a Message Claude Developer Platform · in the page api/messages/create …ing the field. - `oversized_image: optional "downsize" or "error"` What the server does when this image exceeds the model's maximum image size. `"downsize"` (the default) scale… overview Claude Developer Platform · in the page api/overview …plify API integration by handling authentication, request formatting, error handling, and more. **Benefits:** * Automatic header management (authentication, `anthropic-version`, `content-type`) * Ty… rate-limits Claude Developer Platform · in the page api/rate-limits …Short bursts of requests can exceed the limit and trigger rate limit errors. * The following limits are the standard limits for each tier. If you need higher limits, see [Requesting higher limits](ht… service-tiers Claude Developer Platform · in the page api/service-tiers …her requests. This prioritization helps minimize ["server overloaded" errors](https://platform.claude.com/docs/en/api/errors#http-errors), even during peak times. For more information, see [Existing… versioning Claude Developer Platform · in the page api/versioning …Add additional values to the output * Change conditions for specific error types * Add new variants to enum-like output values (for example, streaming event types) Generally, if you are using the AP… Message Batches API Claude Developer Platform · in the page build-with-claude/batch-processing …ported in batch requests. Including any of these returns a validation error: | Parameter | Why… citations Claude Developer Platform · in the page build-with-claude/citations …(or the deprecated `output_format` parameter), the API returns a 400 error. This is because citations require interleaving citation blocks with text output, which is incompatible with the strict J… claude-in-microsoft-foundry Claude Developer Platform · in the page build-with-claude/claude-in-microsoft-foundry …tures against a deployment hosted on Azure return a `400 Bad Request` error by design. Claude Code detects deployments hosted on Azure and automatically adapts its feature set. ## API responses API… claude-on-amazon-bedrock-legacy Claude Developer Platform · in the page build-with-claude/claude-on-amazon-bedrock-legacy …odels, a request that passes the base model ID fails with an HTTP 400 error like the following: ```text wrap Invocation of model ID anthropic.claude-sonnet-4-5-20250929-v1:0 with on-demand throughput… claude-platform-on-aws Claude Developer Platform · in the page build-with-claude/claude-platform-on-aws …iam enable-outbound-web-identity-federation ``` If the response is `[ERROR] (FeatureEnabled) ... already enabled`, the setting is already on for your account and you can move on. Verify and retrieve… sent_count = len(messages sent in the compaction request) Claude Developer Platform · in the page build-with-claude/compaction …content: $(cat content.json) - role: user content: Now add error handling context_management: edits: - type: compact_20260112 YAML ``` ```python Python client = anthrop… compaction-background Claude Developer Platform · in the page build-with-claude/compaction-background …demand#continue-from-the-summary) and [Handle a missing summary or an error](https://platform.claude.com/docs/en/build-with-claude/compaction-on-demand#when-no-summary-comes-back) apply unchanged. ##… compaction-on-demand Claude Developer Platform · in the page build-with-claude/compaction-on-demand …sages. If any remain in front of the block, the request returns a 400 error (`compaction_block_misplaced`). * Send exactly one `compaction` block per request, on every later request. <Warning> Two… compaction-thinking-blocks Claude Developer Platform · in the page build-with-claude/compaction-thinking-blocks …that sends the kept thinking where the API enforces the check: a 400 error by default, or dropped thinking blocks if the request sets `thinking.block_binding.prefix_mismatch_behavior` to `"drop_block… compaction-threshold Claude Developer Platform · in the page build-with-claude/compaction-threshold …content: $(cat content.json) - role: user content: Now add error handling context_management: edits: - type: compact_20260112 YAML ``` ```python Python client = anthrop… context-editing Claude Developer Platform · in the page build-with-claude/context-editing …"content": "Search for the latest developments in quantum error correction and summarize the key breakthroughs." } ], "tools": [ {… context-windows Claude Developer Platform · in the page build-with-claude/context-windows …lock authenticity. If you modify a thinking block, the API returns an error. <Note> Most current Claude models support [interleaved thinking](https://platform.claude.com/docs/en/build-with-claude/t… effort Claude Developer Platform · in the page build-with-claude/effort …ext). Requests that set `thinking: {"type": "disabled"}` return a 400 error at every effort level. Claude Opus 5.5 also supports [changing effort mid-conversation](https://platform.claude.com/docs/en/… This will automatically use the environment variable VOYAGE_API_KEY. Claude Developer Platform · in the page build-with-claude/embeddings …ors by dividing each row by its Euclidean norm. Raises a ValueError if any row has a norm of zero to prevent division by zero. """ row_norms = np.linalg.norm(v, axis=1, keepdim… extended-thinking Claude Developer Platform · in the page build-with-claude/extended-thinking …ls do not support it and reject requests that use it, returning a 400 error. On Claude 4.5 and earlier models that support thinking, extended thinking is the only available thinking mode. Claude Mytho… fallback-credit Claude Developer Platform · in the page build-with-claude/fallback-credit …response = send("claude-opus-4-8", attempt) except BadRequestError as error: if "redemption temporarily unavailable" in error.message: raise # Transient: retry with t… fast-mode Claude Developer Platform · in the page build-with-claude/fast-mode …pus 4.7. Requests to `claude-opus-4-7` with `speed: "fast"` return an error; unlike Claude Opus 4.6 (see the following note), requests do not fall back to standard speed. The model itself remains avai… files Claude Developer Platform · in the page build-with-claude/files …```go Go func downloadFile(client anthropic.Client, fileID string) error { resp, err := client.Files.Download(context.TODO(), fileID, anthropic.FileDownloadParams{}) if err != nil { retur… handling-stop-reasons Claude Developer Platform · in the page build-with-claude/handling-stop-reasons …ason` field is part of every successful Messages API response. Unlike errors, which indicate failures in processing your request, `stop_reason` tells you why Claude completed its response generation.… mid-conversation-effort-example Claude Developer Platform · in the page build-with-claude/mid-conversation-effort-example …"context" "crypto/sha256" "encoding/hex" "encoding/json" "errors" "fmt" "log" "os" "os/exec" "path/filepath" "strings" "sync" "time" "github.com/anthropics/anth… mid-conversation-system-messages Claude Developer Platform · in the page build-with-claude/mid-conversation-system-messages …e`). Referencing a name that is not declared in `tools` returns a 400 error (on the Claude API, with `error.details.error_code` set to `tool_reference_unresolved`). A `tool_addition` block can instead… preserved-thinking Claude Developer Platform · in the page build-with-claude/preserved-thinking …del can't read a block, the API drops it from that request without an error. See [Switching models mid-conversation](https://platform.claude.com/docs/en/build-with-claude/preserved-thinking#switching-… Request 2 caches its request content (not the response) Claude Developer Platform · in the page build-with-claude/prompt-caching …explicit `cache_control` with a different TTL, the API returns a 400 error. * If 4 explicit block-level breakpoints already exist, the API returns a 400 error (no slots left for automatic caching). *… claude-prompting-best-practices Claude Developer Platform · in the page build-with-claude/prompt-engineering/claude-prompting-best-practices …quests with prefilled assistant messages to these models return a 400 error. Model intelligence and instruction following have advanced such that most use cases of prefill no longer require it. Earlie… prompting-claude-fable-5 Claude Developer Platform · in the page build-with-claude/prompt-engineering/prompting-claude-fable-5 …id premature abstraction and half-finished implementations. Don't add error handling, fallbacks, or validation for scenarios that cannot happen. Trust internal code and framework guarantees. Only vali… Delivering work Claude Developer Platform · in the page build-with-claude/prompt-engineering/prompting-claude-fable-5-1 …"content": f"File not found: {path}", "is_error": True, } ) # Send the tool results as the user turn, then a fresh copy of the… prompting-claude-opus-5 Claude Developer Platform · in the page build-with-claude/prompt-engineering/prompting-claude-opus-5 …that matter: ```text wrap Only correct an earlier statement when the error would change the user's code, conclusions, or decisions. State corrections plainly and briefly, then continue the task. For… prompting-claude-opus-5-5 Claude Developer Platform · in the page build-with-claude/prompt-engineering/prompting-claude-opus-5-5 …al model and one-page summary for a transaction or finding and fixing errors in a valuation workbook, and it catches details that are easy to miss in large inputs, such as a date in a long planning th… prompting-claude-sonnet-5 Claude Developer Platform · in the page build-with-claude/prompt-engineering/prompting-claude-sonnet-5 …et_tokens: N}`) is not supported on Claude Sonnet 5 and returns a 400 error. It was deprecated on Claude Sonnet 4.6 and is now removed. Use adaptive thinking with the effort parameter instead. <Note>… refusals-and-fallback Claude Developer Platform · in the page build-with-claude/refusals-and-fallback …e a request. When that happens, you receive a normal response, not an error, with `stop_reason: "refusal"`. Its `stop_details.category` names the policy area (see [What a refusal looks like](https://p… search-results Claude Developer Platform · in the page build-with-claude/search-results …type="text", text="If you encounter timeout errors, first check the configuration settings. Common causes include network latency and incorrect timeout values.",… skills-guide Claude Developer Platform · in the page build-with-claude/skills-guide …alidate the cached prefix if it changes the Skill's description. ### Error handling Handle Skill-related errors gracefully: <CodeGroup> ```bash cURL # This error-handling flow doesn't translate… streaming Claude Developer Platform · in the page build-with-claude/streaming …nts Event streams may also include any number of `ping` events. ### Error events The API may occasionally send [errors](https://platform.claude.com/docs/en/api/errors) in the event stream. For exam… structured-outputs Claude Developer Platform · in the page build-with-claude/structured-outputs …ed-outputs-2025-11-13` beta header. Without it, the API returns a 400 error. The Python SDK (v1.0 and later) does not accept `output_format={...}` on `client.beta.messages.create()` or `count_tokens()… task-budgets Claude Developer Platform · in the page build-with-claude/task-budgets …th-claude/task-budgets#feature-support)). Smaller values return a 400 error. ## Interaction with other parameters * **`max_tokens`:** Orthogonal to task budgets. `max_tokens` is a hard per-request c… thinking Claude Developer Platform · in the page build-with-claude/thinking …`thinking: {type: "disabled"}` with those effort levels return a 400 error. This restriction is enforced on each request. With thinking disabled, Claude Opus 5 can occasionally emit tool calls as pla… thinking-tool-workflows Claude Developer Platform · in the page build-with-claude/thinking-tool-workflows …g-with-tool-use): `tool_choice` options that force tool use return an error with manual extended thinking (`thinking: {type: "enabled"}`); adaptive thinking supports forced tool use. * [Keep one think… thinking-troubleshooting Claude Developer Platform · in the page build-with-claude/thinking-troubleshooting …Diagnose and fix the most common thinking failures: configuration 400 errors, empty or missing thinking blocks, max_tokens stops, and cache misses." --- <Note> To learn how zero data retention (ZDR… token-counting Claude Developer Platform · in the page build-with-claude/token-counting …al number of input tokens. This endpoint returns an `invalid_request_error` for a few inputs that the Messages API accepts: [server tools](https://platform.claude.com/docs/en/agents-and-tools/tool-us… vision Claude Developer Platform · in the page build-with-claude/vision …es exceeding the stricter limit are rejected with an `invalid_request_error` whose message references "many-image requests" and states the current limit in pixels. To stay under the limit on all platf… vision-coordinates Claude Developer Platform · in the page build-with-claude/vision-coordinates …still be rejected when you send it. </Note> ## Turn resizing into an error with `transformations` Pre-resizing only protects your coordinates while your pipeline keeps producing the right sizes. A n… working-with-messages Claude Developer Platform · in the page build-with-claude/working-with-messages …ude Mythos Preview. Setting them to a non-default value returns a 400 error. Omit them from request payloads and use prompting to guide the model's behavior instead. See the [migration guide](https://…