Partial Implementation

Code returned as "done" is actually a stub — a placeholder body, a TODO comment, or a function that claims completion without real logic.

A function or module is declared complete, but the body is a stub. The most common form is a function with pass, return None, throw NotImplementedError, or a single TODO: comment in place of real logic.

Symptoms

• Function signature exists but the body contains only a comment, pass, return, throw new Error("not implemented"), or similar.
• Placeholder values returned (return 0, return {}, return null) where real computation was requested.
• Tests pass only because the test is also a stub, or because the function always returns the fixture value.
• The agent claims a change is "complete" or "implemented" but no meaningful lines of logic were added.

What to do

• Before declaring a task done, re-read every function you added or modified. If the body is a placeholder, the task is not done.
• Search the diff for TODO, FIXME, XXX, NotImplementedError, unimplemented!, pass, lone return or return null. Investigate each hit.
• Run the code end-to-end, not just the type-checker. A stub satisfies the type checker but fails at runtime.
• Compare the implementation against the task description: every bullet of the task should map to concrete lines of logic, not comments.
• If part of the task is genuinely out of scope, say so explicitly rather than stubbing silently.