lens-test

name	lens-test
description	Interpret lenslab analyse JSON, relay only CLI-prescribed capture fixes, and keep the Rust CLI as the only measurement engine. Use when a user wants to assess a lens copy from DNG/TIFF captures, understand copy_assessment support, or get reshoot guidance.

Lens Test

Use this skill to help a user prepare DNG/TIFF lens-test captures, run lenslab inspect and lenslab analyse, interpret the resulting copy_assessment evidence, and recommend the smallest CLI-prescribed reshoot when the result is inconclusive.

Contract

• The Rust CLI measures; the agent interprets and coaches.
• This is the shared skill core. Claude, Codex, opencode, and future harness adapters should point at these instructions rather than copying the interpretation rules.
• Never re-measure, recompute target QA, recalculate decentring asymmetry, or infer optical support from pixels yourself.
• Treat lenslab analyse stdout JSON as the source of truth.
• Keep measured facts separate from inferred support.
• Do not give keep/return advice in this slice.
• Do not call a lens centred or decentred when copy_assessment.state is inconclusive.

Input Preparation

Accept either explicit capture files or one flat capture folder.

For explicit files:

• Keep the user-supplied order unless the user asks otherwise.
• Reject paths that are not local files before running the CLI.

For one folder:

• Read only direct children.
• Keep files ending .dng, .tif, or .tiff, case-insensitively.
• Sort accepted files by path before analysis.
• Do not recurse.
• Ignore sidecars and other raw extensions such as .nef for folder expansion.
• If no direct child DNG/TIFF files exist, ask for usable files instead of running analysis.

CLI Flow

1. Locate lenslab on PATH.
2. If lenslab is unavailable, stop and tell the user the CLI is not installed or not on PATH. Do not clone the repository, build from source, or install tools unless the user explicitly asks for setup work.
3. Run lenslab inspect <representative-file> before analysis.
4. Use inspect output to surface early blockers: mixed lens/body identity, missing aperture spread, or correction provenance that makes the input unsuitable.
5. Run lenslab analyse <paths...> with explicit files only. Do not pass folders directly to analyse.
6. Parse JSON from stdout. Treat stderr as diagnostics.
7. Require schema_version: "0.1-copy-assessment-support" for this skill version. On mismatch, tell the user to update the binary or skill instead of parsing best-effort.

Interpretation

Read these fields first:

• copy_assessment.state
• copy_assessment.evidence
• copy_assessment.blockers
• copy_assessment.reshoot

State mapping:

• supports_centred: lead with centred support, then explain which gates passed.
• supports_decentred: lead with decentred support, then explain the asymmetric evidence and any counterevidence that was ruled out.
• inconclusive: lead with inconclusive and explain the blockers. Do not call the lens centred or decentred.

Use references/interpreting-results.md for the full interpretation rules and references/reshoot-coaching.md for blocker-to-reshoot wording.

Reshoot Coaching

When support is blocked or inconclusive:

• Show a prioritised blocker shortlist.
• Treat copy_assessment.reshoot as a strict allowlist for capture changes, replacement input, and protocol advice.
• When the list is non-empty, show only its actions and prefer the smallest one that can unblock hard support.
• When the list is empty, make the entire next-step content: "The CLI prescribed no capture action." Do not suggest ideal input or a shooting protocol, or tell the user to rerun.
• A generic request such as "what should I do next?" does not override an empty list. Reference references/shooting-guide.md only when the user explicitly asks for the general protocol, and make clear that it is not advice derived from this run.

Required Output Shape

Keep the answer short and factual:

1. Support state: centred support, decentred support, or inconclusive.
2. Evidence: measured facts and inferred support, labelled honestly.
3. Blockers or counterevidence.
4. Prioritised reshoot actions only when copy_assessment.reshoot is non-empty.
5. Explicit non-claims when the evidence does not support a hard answer.

Use the examples in references/examples/ as the interpretation contract. The checklists are the marking scheme; exact prose does not need to match.