FLX-3108: the bundle directory holds a file this engine does not recognise
Family: seam/conformance (the 3000 band)
A bundle directory holds two classes of file and no third. Its inputs are the documents the loader reads: *.flux.yml, *.flux.yaml, *.fluid.yml, *.fluid.yaml and flux.lock. Its products are the files a pack writes beside those documents, flux-manifest.json and its detached signature, which are recognised and left out of inputDigest because their content is a function of the inputs. Any other regular file ends the command here, naming the file, before a digest is taken. KERNEL-SPEC section 11 makes inputDigest the value apply and verify bind a run to, so a file that arrives beside the documents must neither move that value quietly nor be hashed as an input without anyone deciding it is one. Delete the file, or keep it outside the bundle directory. If it is a document kind a newer FLUX version defines, this engine is too old to read the bundle and the fix is to upgrade the engine rather than to delete the document.
Look it up offline
$ fluxsim explain FLX-3108
Every code is listed in the error index.