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root-context-budget

Off by default: once a workspace turns it on, it reports a session's main thread whose context has grown past its level's size.

What it catches

A session's main thread whose context has grown past its level's size.

Why

Every call of a session re-sends its whole context, mostly as cache reads, so its cost grows with the square of its length, and a main thread that does its own reading pays for each result on every call after it. The size is the last usage the main transcript recorded, read after each call. At light it advises once at half the model's window, and says nothing for a model the table does not know; at standard it advises once at a fixed size, and at strict at a lower one, each lower when the account bills per token than on a subscription quota. The advice names magus job fork and a spawn. It never refuses: size tunes how often a session hears this, never whether its work is refused, which orchestrator-groundwork decides by the session's role. A tokens parameter replaces the level's sizes. It judges only the unleased main thread. A call whose output is a ref or one line is never judged by this rule, so a main thread past its budget can still build ./magus and file its work: the bootstrap build command, magus run or magus affected with -s or --silent, magus run go-build or go::go-build, magus job fork, exit, apply and wait, magus query output --identity, any magus command asked for -o name or -o template=, git commit, cherry-pick and branch, git status -s, and git log --oneline with a count (-n, --max-count or -N). A line that changes directory first is judged by the rest of it.

Default and override

By default this rule takes the decision off. A workspace sets it by name, in its root magusfile, to advise or off:

magus\guard.builtins({"root-context-budget": "advise"})

A loosening takes effect once it is committed; a tightening applies at once.

Seeing it

A verdict names its rule in brackets, which is how you got here:

advise [root-context-budget]: ...

magus describe rule root-context-budget prints the same entry at a terminal, and magus describe rules lists every rule this workspace enforces.

See also

guardrulesroot-context-budgetoff
Last updated (29d8b3de)
Glossary

Workspace

The magus root directory that owns a set of projects and shared config; the unit magus operates over. Workspace in full.

Magusfile

The magusfile.buzz that declares a project's targets (as export funs) and binds its spells. Magusfile in full.

Buzz

The language magusfiles are written in (the .buzz engine). Buzz in full.

Cache

The content-addressed store magus consults before running a target, so unchanged work is skipped. Cache in full.

Affected

The set of projects touched by a change; magus affected <target> runs a target only over them. Affected in full.

CI

An ordinary target you compose yourself with ctx.needs; magus does not hardcode its stages. It is the anchor magus affected ci keys off, and ci strips the rw charm. CI in full.

Agent

A model working through an agent host such as Claude Code, Codex, Cursor or OpenCode. magus treats an agent as one more caller of its CLI, MCP tools and console, held to the same checks as a person. Agent in full.

Session

An agent host's conversation, by the id the host delivers to its hooks. magus never mints one: a record with no session is unattributed, and the OS user it carries says whose account ran it. Session in full.

Window

The terminal a command runs in. It keys fire-once notices for a caller no host gave a session, and is never recorded as a session. Window in full.

Job

The unit of delegated work, and one row of the job store: what an orchestrating agent handed out, with its goal, the checkpoint it was cut against, the paths it may write or must not touch, and the one check it runs. A job's holder is either a session, for work an orchestrator handed out, or the daemon, for its own maintenance. The store records; the agent guard is what reads those facts back when grading a write. Job in full.

Run

One target executing under one magus invocation, such as magus run test web or magus affected ci. A run keeps its captured output behind an output reference. Every magus run is a run whether or not any job asked for it; see Job for how the two relate. Run in full.

Lease

The grant a holder takes on a job: the write and read paths that job declared, enforced in the checkout that took it with magus job exec. A job is the piece of work; a lease is permission over it. Lease in full.

Conventions

This page uses none of the site's convention markers. The full set is on the conventions page.