claude-code - 💡(How to fix) Fix [BUG] Cowork: project creation fails with generic error when name contains special characters (e.g. `|`)

When creating a new project in Cowork, using certain special characters in the project name (e.g. pipe |) causes creation to fail with a generic "Failed to create project. You can try again" message. The error gives no indication that the problem is an invalid character in the name — users are left guessing whether it's a server issue, a network issue, or their own fault. Expected: Either (a) accept the character, or (b) show a specific validation error like "Project names cannot contain: | / \ : * ? " < >" before submission — or reject the character inline as the user types.

Error Messages/Logs

Observed: Generic "Failed to create project. You can try again" toast. Project is not created. Retrying with the same name reproduces the error indefinitely. Observed: Generic "Failed to create project. You can try again" toast. Project is not created. Retrying with the same name reproduces the error indefinitely. Expected: Either (a) accept the character, or (b) show a specific validation error like "Project names cannot contain: | / \ : * ? " < >" before submission — or reject the character inline as the user types. When creating a new project in Cowork, using certain special characters in the project name (e.g. pipe |) causes creation to fail with a generic "Failed to create project. You can try again" message. The error gives no indication that the problem is an invalid character in the name — users are left guessing whether it's a server issue, a network issue, or their own fault. Observed: Generic "Failed to create project. You can try again" toast. Project is not created. Retrying with the same name reproduces the error indefinitely. Expected: Either (a) accept the character, or (b) show a specific validation error like "Project names cannot contain: | / \ : * ? " < >" before submission — or reject the character inline as the user types. The error message suggests a transient issue ("you can try again"), so users retry with the same name instead of editing it. I only found the cause by trial and error. A specific validation message would save real time and reduce support load.

• Show the specific invalid character(s) in the error
• Or: sanitize the name automatically and warn the user

TL;DR

Validate project names client-side to prevent creation failures due to special characters.

Guidance

• Validate project names against a set of allowed characters before submission to prevent server-side errors.
• Display specific validation errors to users, such as "Project names cannot contain: | / \ : * ? " < >", to improve user experience.
• Consider sanitizing project names automatically and warning users of changes made to their input.
• Review the Anthropic API documentation to ensure compliance with project name requirements.

Example

const invalidChars = /[|\/\\:*?"<>]/;
if (invalidChars.test(projectName)) {
  // Display error message to user
  console.error("Project names cannot contain: | / \\ : * ? \" < >");
} else {
  // Proceed with project creation
}

Notes

The suggested fix assumes that the Anthropic API has specific requirements for project names. It's essential to review the API documentation to ensure compliance.

Recommendation

Apply a client-side validation workaround to improve user experience and reduce support load, as the root cause of the issue seems to be related to invalid characters in project names.