I3171 — The compiled context names source ranges with their reason and confidence, not only whole objects of the layer

○READY wave 0 · p3 · deep-work profile · parallel safe

Part of development-runtime — The runtime has a development surface.

Objective

Extend devcontext so a request with scope paths yields source entries (path, line range, symbol where known, reason, confidence, cost) beside layer objects, and measure the tokens saved against whole-file reading on a large file.

Why

2026-10-13: a discovery delegate should return a manifest of paths, symbols and ranges rather than file contents, keeping the parent's context small. devcontext's ContextEntry is a layer object with provenance (devcontext/model.rs). Milestone development-runtime is named by no intent, so this issue is derived maintenance and serves no criterion (intent-bound-work#exemption-is-typed). Sources: chatgpt-majordomus:c252#2, chatgpt-majordomus:c252#5.

Current state

Entries are layer objects only.

Desired state

Source-range entries with provenance, budgeted like the rest.

Scope

• apps/majordomus-cli/src/devcontext
• apps/majordomus-cli/src/capability/builtin/devcontext.rs
• docs/CONTEXT.md

Out of scope

• An LSP dependency

Dependencies

None. This issue is a root of the graph.

Acceptance criteria

• A large-file request is answered by ranges
• The measured cost is lower than whole-file reading and the answer says by how much

Validation

• cargo test --manifest-path apps/majordomus-cli/Cargo.toml --lib devcontext::

Evidence required

• test_context_source_ranges

Evidence

None recorded. Every token above needs a command or an artifact behind it before this issue can be completed; narrative is refused.

Timeline

started

—

verified

—

completed

—

Those three fields, the evidence above and the state of the dependencies are all the status is made of. There is no status field to disagree with them.

Canonical record: .ai/repo/project/issues/I3171.yaml. Read it back with majordomus plan show I3171.