---
title: "Task Routes And Lenses"
description: "Canonical Keel reference: Task Routes And Lenses."
image: "https://skills.lencx.me/og.png"
---

> Documentation Index
> Fetch the complete documentation index at: https://skills.lencx.me/llms.txt
> Use this file to discover all available pages before exploring further.

# Task Routes And Lenses

> Rendered directly from the [canonical source](https://github.com/lencx/skills/blob/main/skills/keel/references/task-routes-and-lenses.md).

This file contains branch-specific concerns only. SKILL.md owns working-state
selection, the constructive loop, Closed/Open completion, and sections 1–8.

## Task routes

Choose a route after the working state and initial framing are clear. A route
organizes deeper evidence; it does not preselect a solution or require a new
artifact. If another route contributes a material concern, import that concern
without duplicating the full route.

| Route | Use when | Branch-specific concern |
| --- | --- | --- |
| `greenfield_design` | **Decision:** goals and external constraints exist without inherited repository architecture | apply SKILL.md's greenfield evidence rule; state assumptions, decision authority, and the cheapest way to test the result |
| `architecture_review` | **Judgment:** a design, RFC, change set, or existing system needs a load-bearing adequacy, conformance, feasibility, or integration verdict | map material claims to evidence or explicit unknowns, preserve focused ownership, and transition to Decision before proposing authorized improvements |
| `boundary_change` | **Decision:** a contract, schema, export, flag, entry surface, or compatibility promise is added, widened, moved, or removed | identify affected consumers, decision authority, compatibility or cutover commitment, and proportionate verification |
| `structural_refactor` | **Decision:** a load-bearing module or seam is split, merged, moved, rewritten, or generalized | apply SKILL.md's Target scope rule; preserve contracts and the deletion path |

Complete a selected route only when its branch-specific concern appears in the result or is recorded as an Open unknown. Treat SKILL.md sections 1–8 as the sole source of cross-cutting obligations.

If evidence reopens a materially different direction, return to comparison
instead of finishing the current route by inertia.

## Rewrite branch

For a `structural_refactor` that proposes a rewrite, apply SKILL.md's Target
scope rule, derive the target terminal invariant from representative evidence,
and start with the smallest independently replaceable implementation slice and
its preserved contracts. Expand only when a bounded migration cannot close
safely or carries greater evidenced migration or recovery risk.

A whole-target replacement is supported only when the target is bounded; its
surfaces, dependents, state, and preserved contracts are known; acceptance
evidence maps those contracts and the terminal invariant; runnable rollback or
retreat evidence exists; and representative, materially distinct smaller slices
do not reach the same invariant at equal or lower evidenced risk. Do not require
proof against unbounded hypothetical slices.

## Optional review prompts

SKILL.md sections 1–8 are the source of these concerns. Ask only questions whose
answers can change the recommendation or a material risk:

- Which concrete surfaces carry compatibility promises?
- Which authority, ownership, writer, dependency, or projection relations
  actually exist?
- Which negative or time-axis outcome could invalidate the direction?
- Which guard, migration, recovery, or deletion evidence is necessary at this
  blast radius?
- What new concept or layer is added, what does it retire, and is a simpler
  direction still viable?

Group inapplicable concerns without producing an empty matrix.

Source: https://skills.lencx.me/skills/keel/reference/task-routes-and-lenses/index.mdx