Add-Model PR Review

Use this skill when a reviewed PR appears to add, port, or substantially modify a FastVideo model family, model variant, first-class model component, checkpoint conversion, model pipeline, or local parity coverage.

This is a review skill, not an implementation workflow. Do not run /add-model or start writing missing port code during review. Use the add-model skill stack as a rubric for findings.

Trigger Paths

Trigger this skill if git diff --name-only <base>...HEAD includes any of:

• fastvideo/models/dits/, fastvideo/configs/models/dits/
• fastvideo/models/vaes/, fastvideo/configs/models/vaes/
• fastvideo/models/encoders/, fastvideo/configs/models/encoders/
• fastvideo/models/schedulers/, fastvideo/configs/models/schedulers/
• fastvideo/models/upsamplers/, fastvideo/configs/models/upsamplers/
• fastvideo/models/audio/, fastvideo/configs/models/audio/
• fastvideo/pipelines/basic/, fastvideo/configs/pipelines/
• fastvideo/registry.py, fastvideo/api/sampling_param.py
• scripts/checkpoint_conversion/
• examples/inference/basic/
• tests/local_tests/, especially component or pipeline parity tests
• fastvideo/tests/ssim/ or other quality-regression tests for generated media

Also trigger when the PR title/body claims a new model, model variant, VAE, encoder, scheduler, conditioner, pipeline, conversion script, or generated-media quality baseline even if the path list is incomplete.

Review Inputs

Read these add-model references as review checklists:

• ../add-model/SKILL.md: phase gates and final handoff requirements.
• ../add-model/shared/common_rules.md: token/auth safety, production import boundaries, state files, and skip/pass semantics.
• ../add-model/contracts/final_handoff.md: final evidence expected from a complete port.
• ../add-model/contracts/component_context.md and ../add-model/contracts/component_skill_handoff.md: component evidence and parity-debug expectations.
• ../add-model/contracts/conversion_request.md and ../add-model/contracts/conversion_handoff.md: conversion evidence, strict-load status, config validation, and retry context.
• ../add-model/contracts/pipeline_context.md and ../add-model/contracts/pipeline_handoff.md: pipeline class/stage/config/ preset/registry/example evidence.

Then read only the satellite skill(s) that match touched areas:

• DiT/transformer changes: ../add-model-03-port-dit/SKILL.md.
• VAE changes: ../add-model-04-port-vae/SKILL.md.
• Encoder/conditioner changes: ../add-model-05-port-encoder/SKILL.md.
• Scheduler/upsampler/vocoder/other components: ../add-model-06-port-generic/SKILL.md.
• Component parity tests: ../add-model-02-parity/SKILL.md.
• Checkpoint conversion: ../add-model-07-conversion/SKILL.md.
• Pipeline/config/presets/registry/examples: ../add-model-09-pipeline/SKILL.md.
• Prep/state docs: ../add-model-01-prep/SKILL.md.

Required Review Lanes

For a full model-family or model-variant PR, cover all lanes. For a component-only PR, cover the component, conversion/parity as applicable, and the documented downstream consumer.

1. Scope and source-of-truth lane: Verify the PR clearly identifies the official reference, weights/revision, supported variants, modalities, output heads, and any approved scope cuts.

2. Component lane: Verify each required component is FastVideo-native or has a documented and accepted lazy-wrapper exception. Check bucket/config inheritance, EntryClass, state-dict surface, reused-component evidence, and output heads.

3. Conversion lane: Verify mappings are derived from prototype key/shape dumps, source layout is supported, skipped keys are intentional, emitted configs validate through production paths, component strict-load status is recorded, model_index.json library tokens match loaders, and revisions are pinned when converting from HF.

4. Component parity lane: Verify local parity tests exist for every required component, including reused components. Scaffolds may skip in CI, but the PR must provide local non-skip PASS evidence or an explicit accepted blocker.

5. Pipeline lane: Verify stage order, required modules, _class_name / EntryClass.__name__ resolution, config defaults, presets, SamplingParam fields, registry registration, examples, smoke tests, and pipeline parity.

6. Quality and evidence lane: Verify media quality regression is added or explicitly deferred, examples run, generated outputs are non-corrupt, tests/local_tests/<family>/README.md and PORT_STATUS.md are current, and final blockers are surfaced in the review.

Findings To Prioritize

Prioritize review findings in this order:

• Missing or skipped required component parity without accepted blocker.
• Pipeline parity/smoke/example missing or skipped for a pipeline PR.
• Conversion emits unloadable or unvalidated configs/weights.
• Wrong model_index.json _class_name, component library token, or registry class resolution.
• Runtime diffusers/transformers model-class imports for components that own weights or numerical behavior.
• Dropped modalities, output heads, variants, or conditioning streams without explicit approval.
• Reused FastVideo component lacks exact definition/instantiation proof or non-skip parity.
• Public generation kwargs/preset defaults missing from SamplingParam.
• Tests only check shapes, importability, or successful generation without numerical/media comparison.
• Tokens, credentials, reference clones, staged weights, or generated bulk assets committed to the PR.

Output Format

Write normal code-review findings first, ordered by severity. Include file and line references from the PR diff when possible.

Use this phrasing for missing add-model evidence:

This PR does not satisfy the add-model <component|conversion|pipeline|final>
gate because <specific required evidence> is missing. The risk is <runtime load,
numerical parity, dropped output, registry resolution, etc.>.

Keep the summary short. Mention which lanes were reviewed and which could not be verified because assets, GPU time, or external credentials were unavailable.