Every command in moodle, edstem and ontrack follows the same shape:
edstem threads search 12345 assignment deadline, ontrack tasks set UNIT TASK working_on_it, and moodle activities list UNIT are all instances of the same pattern: a noun (what you’re working with), a verb (what to do with it), then scope and identifiers.

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Verbs

The verb vocabulary is shared across all three CLIs and stable across releases:
A domain command at noun depth must use one of these — there’s no other verb to type. auth and skills are the exception — they’re action groups (login, status, logout, keepalive under auth; generate, add under skills), not nouns with verbs, so their subcommands carry no verb field.

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Default verbs by arity

Typing the verb is usually optional. The CLI looks at how many arguments follow a noun and inserts the matching default verb for that count — edstem units (zero arguments) becomes edstem units list; edstem units UNIT (one argument) becomes edstem units show UNIT. This still works when flags are mixed in with the arguments.

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Noun aliases

units is the canonical enrolment noun in all three CLIs; courses and projects are equivalent aliases everywhere. moodle courses and moodle units are the same command.

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References: UNIT, TASK, SECTION

A UNIT argument accepts whatever the site itself uses to identify it — a numeric id, the exact code, or the exact name — and, in moodle, a URL. None of the three tools assumes a code follows a particular format (letters plus digits, a fixed length, and so on): they resolve what you typed against the site’s own unit list, because that list is the only thing that’s actually true across institutions. Run <tool> units to see the vocabulary a given site uses. TASK (OnTrack) and thread/lesson references (Ed) work the same way: a short form you’d recognize from the site, or a numeric id. SECTION (Moodle only) is a section number or name inside a unit. A bare number matches that number in the site’s own section name, not a sequential index — a reference to 7 never matches a section actually named 17.

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Ambiguity

When a reference matches more than one thing, the CLI never guesses. At a terminal, you get a picker; anywhere else, the JSON error carries a candidates array alongside the error code, so a script or agent can present the choice instead of failing blind. Moodle, for example, reports code: "ambiguous" with a candidates list of { id, name, code } when more than one unit or section matches, and code: "not_found" when none do. See Errors and exit codes for how that shows up in the JSON output.

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Moodle’s extra porcelain

Moodle layers two conveniences on top of the shared model that the other two CLIs don’t have:
  • moodle UNIT [SECTION] — a bare unit (and optional section) reference at the top level, without a noun, opens that unit directly.
  • Pasting a Moodle URL as the target: moodle 'https://moodle.example.edu/course/view.php?id=34637' and moodle download 'https://moodle.example.edu/mod/resource/view.php?id=91234' --dest ./file.pdf both work, because the CLI recognizes course, forum, assignment, quiz, resource, page, folder and grade-report URLs and resolves them the same way it resolves a typed reference.

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commands --json as self-description

Every CLI in the family can describe its own commands as data: moodle commands --json, edstem commands --json, ontrack commands --json. The output includes every command’s aliases, positional arguments, options, enum values, nested commands and a mutating flag — this is what skills generate reads to build each tool’s SKILL.md. A trimmed excerpt from ontrack.commands.json:

Output formats

What the table and JSON forms of a command’s output look like.