mpt CLI

The mpt binary validates and edits multi-part-text (.mpt) documents. Normative grammar lives in RFC-0001.

Installation

From the vyutils repository:

target/debug/mpt

cargo build -p mpt
cargo run -p mpt -- validate path/to/file.mpt

Command tree

Run mpt tree for a concise snapshot of every subcommand, positional argument, and flag. The tree is generated from the CLI definition, so it stays in sync with mpt --help.

mpt tree

Example output (abbreviated):

mpt
├── validate <path>
├── canonicalize <path>
├── merge <input>…
│   └── -o, --output <output>
├── tree
└── part
    ├── extract <path> <id>
    │   ├── --full
    │   ├── --header
    │   └── -o, --output <output>
    ├── add <path> <id>
    │   └── …
    └── remove <path> <id>
        └── …

Synopsis

mpt validate <path>
mpt canonicalize <path>
mpt merge <input>… [-o <path>]
mpt part extract <path> <id> [-o <path>] [--header | --full]
mpt part add <path> <id> [options]
mpt part remove <path> <id> [options]

Conventions

Topic	Behavior
Stdout default	Mutating commands (add, remove, merge without -o) print the canonical document to stdout.
In-place	--in-place rewrites the input file (add, remove only). Conflicts with -o.
Canonical output	Serialize uses LF line endings, omits default format = …, and omits default option-map keys (e.g. csv delimiter = ",").
Exit code	0 on success; non-zero on parse, validation, or edit errors.
Errors	Messages on stderr; format path: reason.
parts in file header	Tool-maintained; refreshed on canonical serialize and part add / part remove. Other commands warn if declared parts ≠ actual count.

Provenance and license fields belong in the file header TOML payload (# line comments OK). Do not hand-edit parts = <n>.

mpt validate

Parse and validate structure. Does not interpret payload formats (toml, yaml, etc.).

mpt validate <path>

Argument	Description
<path>	Path to an .mpt file.

mpt canonicalize

Parse and print the canonical serialized document to stdout.

mpt canonicalize <path>

Argument	Description
<path>	Path to an .mpt file.

mpt merge

Concatenate parts from multiple documents into one, preserving order within each input file.

mpt merge <input>… [-o <path>]

Argument / flag	Description
<input>…	One or more .mpt files (at least one).
-o, --output	Write merged document to <path>. Default: stdout.

File headers on merge

Situation	Result
Only the first document has a file header	That header is kept.
Only a later document has a file header	Its header is adopted.
Two or more documents have a file header	Error: cannot merge: more than one file header across inputs.
No document has a file header	Merged document has no file header.

Part ids must be unique across all inputs; duplicates produce duplicate part id.

mpt part extract

Extract content from a named part.

mpt part extract <path> <id> [-o <path>] [--header | --full]

Argument / flag	Description
<path>	Path to an .mpt file.
<id>	Part id.
-o, --output	Write to <path>. Default: stdout.
--header	Output the part-level header payload only. Error if the part has no header block.
--full	Output a standalone single-part .mpt document. Conflicts with --header.

Default (no flags): part body bytes only.

Stdout and -o / --output write the stored payload exactly as parsed (including a trailing LF when the last content line had one).

mpt part add

Insert a new part. Body is read from --body-file or stdin when omitted.

mpt part add <path> <id> [options]

Flag	Description
--format <name>	Body format on the part envelope. Default: text.
--body-file <path>	Body payload file. Default: stdin.
--header-file <path>	Optional part-level header payload file.
--header-format <name>	Header payload format when --header-file is set. Default: toml.
--before <id>	Insert before existing part <id>.
--after <id>	Insert after existing part <id>.
-o, --output	Write updated document to <path>.
--in-place	Rewrite <path>. Conflicts with -o.

If neither --before nor --after is set, the part is appended at the end.

Registered format names: toml, text, yaml, json5, xml, vyasa, csv.

Part-open option-map (TOML inline table) is parsed and canonicalized with the document. v1 csv key: delimiter (default ","). There is no CLI flag to set it yet; put it on the envelope line in the file.

mpt part remove

Remove a part by id.

mpt part remove <path> <id> [options]

Flag	Description
-o, --output	Write updated document to <path>.
--in-place	Rewrite <path>. Conflicts with -o.

Cannot remove the last remaining part.

Library

The same operations are available from the mpt Rust crate:

Module / symbol	Role
parse, to_string	Parse and canonical serialize
merge	Merge documents
add_part, remove_part, find_part	Part edits
InsertPosition	End, Before(id), After(id)

See also

• RFC-0001 — mpt format
• How-to: edit parts