What this error means

Anthropic SDK strips directory paths from filenames in multipart uploads — my-skill/SKILL.md becomes SKILL.md, breaking skills.versions.create() is a Anthropic API failure pattern reported for developers trying to fix anthropic sdk stripping file paths during multipart upload for skills api. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

4 comments. SDK's getName() does val.split(/[\\/]/).pop() with stripPath=true default. Transforms my-skill/SKILL.md → SKILL.md. Breaks beta.skills.versions.create() API which requires top-level directory structure. Affects skill/agent development workflows.

Common causes

  • The SDK's internal uploads.js getName function strips directory paths by default (stripPath=true). This breaks client.beta.skills.versions.create() which requires files to maintain their directory structure (e.g., my-skill/SKILL.md). Developers get API errors with no obvious cause.
  • 4 comments. SDK's getName() does val.split(/[\\/]/).pop() with stripPath=true default. Transforms my-skill/SKILL.md → SKILL.md. Breaks beta.skills.versions.create() API which requires top-level directory structure. Affects skill/agent development workflows.

Quick fixes

  1. Confirm the exact error signature matches Anthropic SDK strips directory paths from filenames in multipart uploads — my-skill/SKILL.md becomes SKILL.md, breaking skills.versions.create().
  2. Check the Anthropic API account, local tool state, and provider configuration involved in the failing workflow.
  3. Compare the failing environment with a known working setup, then change one configuration value at a time.

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.