[Bug]: `twprojects-list_tasks` / `get_task` fail to decode responses containing date-only fields — one task with a due date breaks the whole endpoint

[thejimbirch]

📝 What's the bug?

twprojects-list_tasks and twprojects-get_task fail whenever the Teamwork API response contains a date-only value (e.g. a task due date like 2026-10-13). The server decodes timestamps with the RFC3339 layout only, so any YYYY-MM-DD field aborts the entire response.

Error: MCP error 0: failed to list tasks: failed to handle response:
failed to decode list tasks response: parsing time "2026-10-13" as
"2006-01-02T15:04:05Z07:00": cannot parse "" as "T"

Because one bad record poisons the whole page, list_tasks and get_task are unusable for any project where at least one task has a due date — which in practice is nearly every active project.

✅ What should happen?

Date-only values in API responses (e.g. a task due date of 2026-10-13) should decode successfully — the decoder should accept both 2006-01-02 and RFC3339 layouts. Ideally a single malformed record should not fail the entire response.

❌ What actually happens?

The response decoder only accepts full RFC3339 timestamps, so any date-only field aborts the whole call. Because one bad record poisons the entire page, list_tasks and get_task are unusable for any project where at least one task has a due date — in practice, nearly every active project. Our only workaround was reconstructing task state from list_activities and comment threads.

🔄 How to reproduce

1. Have a project with at least one task that has a due date (ours: project 909851).
2. twprojects-list_tasks(project_id=909851) → decode error (see error output).
3. Also fails scoped to a tasklist (tasklist_id=2672970) and with completed_after filters — the failing value changes (2025-10-20, 2025-12-22) but the error is identical.
4. twprojects-get_task(id=<task with due date>) fails the same way.

Unaffected in our testing: list_tasklists, list_activities, list_notebooks, list_comments.

💻 Code sample

twprojects-list_tasks(project_id=909851)

🚨 Error message/output

Error: MCP error 0: failed to list tasks: failed to handle response:
failed to decode list tasks response: parsing time "2026-10-13" as
"2006-01-02T15:04:05Z07:00": cannot parse "" as "T"

🐹 Go version

Unknown (hosted connector)

📦 Server version

tbd

💻 Operating System

macOS

🔐 Authentication method

OAuth2

🌍 Environment

• This happens in a production environment
• This happens in a development environment
• This happens with a self-hosted Teamwork instance
• This happens with teamwork.com (cloud)
• This happens consistently (every time)
• This happens intermittently (sometimes)

📎 Additional context

Observed via Claude/Cowork's MCP tool-calling interface. This is a response-side decoding failure, distinct from request-side parameter validation issues.

🔧 Troubleshooting checklist

• I have updated to the latest version of the server
• I have checked the API documentation at https://apidocs.teamwork.com/
• I have searched existing issues for similar problems
• I have verified my API token/credentials are valid

[rafaeljusto]

Hi @thejimbirch , thanks for raising this issue! There was a fix related to this in PR #361. Maybe you are running an outdated version? It was released with v1.21.6.

[thejimbirch]

Most likely. We found that it doesn't get updated if it is running, which it always is! I'll close this out and re-open if it happens again.

Thanks!