Glossary

The vocabulary you meet across these docs, defined once.

Index. The persistent semantic graph of a workspace that Fuse builds with Roslyn and keeps in a single SQLite file at .fuse/fuse.db, reused across calls so the analysis cost is paid once.

Warm host. The running server process that keeps the index loaded between calls, so a multi-call task does not rebuild or reload the graph each time.

Node. One indexed element of the graph: a type, a member, a route, a DI registration, or an options binding.

Edge. One typed relationship between nodes: calls, implements, injects, handles, or binds.

Localize. Rank the candidate files and symbols for a task, with reasons and token costs and no bodies, as the cheap first step of an open-ended request. See Scoping.

Resolve. Deterministically map a name to its real target by walking the graph: a service to its DI implementation, a request to its handler, a route to its action, a config section to its options type, or a symbol to its declaration.

Blast radius. The set of code a change semantically impacts: the callers, DI consumers, route and request handlers, options consumers, and tests reachable from the changed files. See Scope a pull request.

Token. The unit a language model reads; a model's context window is measured in tokens, so a context plan's token count decides how much of the window it consumes and what it costs.

Reduction. How Fuse renders source in fewer tokens without changing what it means, ranging from removing comments and whitespace up to dropping method bodies. It is the rendering step, not the product core. See Reduction levels.

Render tier. The fidelity at which a file is emitted: full bodies, compressed source, or signature-only skeleton. A context plan can mix tiers across files to fit a budget.

Skeleton. A render tier that keeps class, interface, and method signatures and removes method bodies; across the recorded four-repository corpus it removes 38 to 44 percent of tokens and retains 96.3 to 99.4 percent of public and protected method-name keys.

Scoping. Narrowing a context request to the code a task needs (by localizing, resolving wiring, or diffing a git change) and expanding through the typed graph. See Scoping.

Seed. The starting node or file set a scoping step expands from before following typed edges.

Manifest. The header on every context plan that lists each included file with its token cost, so a reader or agent can judge the shape and cost before reading any body.

Provenance. The per-file annotation that records why a file is present: the seed and the edge chain that pulled it into the plan.

Round-trip. One read-decide cycle an agent makes while examining a repository; the recorded loop benchmark counts build and test calls separately and does not establish a general reduction in round-trips. See The iterative workflow.

Session-delta. A way to skip resending files an agent already has: pass a sessionId across calls in the same task and Fuse omits files it sent earlier (tracked by content hash), so multi-turn refinement does not re-pay tokens. See Sessions and deltas.

Roslyn structural analysis. The C# parse-tree path that drives indexing, skeletons, dependency edges, type location, route maps, and semantic markers. Regex still handles content reduction, the project graph, and pattern detectors. See Roslyn structural analysis vs regex.

Use the Terms

Run fuse context ./src --seed OrderService --max-tokens 15000. In its manifest, identify the seeds, render tiers, token costs, and provenance before reading the emitted bodies.