Hi ¥Yuan,

Your ProofScaffold you are describing is essentially an instance of “MathOps”!

TL;DR: I have developed the `arrowgram` commutative-diagrams editor
https://hotdocx.github.io/arrowgram then I setup GPT-5.3-Codex inside
my AI workspace to read the JSON text of those diagrams and generate
the `emdash` proof assistant for lax ω-categories
https://github.com/hotdocx/emdash (and to generate its report
https://hotdocx.github.io/r/26043CPAL64001 as a book/slides with
embedeed `arrowgram` diagrams), and you can try (and clone) my shared
AI workspace and fund it at GetPaidX.com a.k.a.
https://LastRevision.pro/r/26044DLGJ77000 — and probably, you should
disregard the rest of this email.

Bye.

---

    APPENDIX:

What is MathOps? Indeed, as soon as you can setup some « MathOps »
(i.e. math DevOps engineering) for a long-running “LLM ↔
proof-checker” feedback loop then autoformalization (e.g. “≈130k lines
in two weeks”) is expected (strangely, Terminal-Bench 2.0 has no such
benchmarks!).

For category theory, the “proof-checker” (i.e. computational logic)
question has been solved since Kosta Dosen “Cut-Elimination in
Categories” (1999), but the tools to easily specify/implement it were
not available until Frédéric Blanqui's Lambdapi logical framework
(rewrite/unification rules) and:

emdash 2 — Functorial programming for strict/lax ω-categories in Lambdapi
https://github.com/1337777/cartier/blob/master/cartierSolution19.lp
(99% generated by AI, lol)
https://hotdocx.github.io/r/26043CPAL64001

And with good “mathops/devops engineering”, a general LLM such as
GPT-5.3-Codex with Codex CLI has succeeded in coding this whole ≈4k
lines file `cartierSolution19.lp` from just text prompts containing
`arrowgram` commutative diagrams which hinted at this “dependent
hom/arrow/comma category” construction:

## 1) Dependent arrow/comma/hom for a dependent category and
“stacking” pasting diagrams

We use displayed/dependent categories over a base category `B` (i.e. a
fibration `E : B → Cat`, or a more general isofibration `E → B`
without transport/arrow-action).

For `b₀ ∈ B` and `e₀ ∈ E(b₀)`, the dependent hom/comma/arrow-category
is the functor:
- `Homd_E(e₀, (–,–)) : E ×_B (Hom_B(b₀, –))ᵒᵖ → Cat`
- notations: `Homd_E : Π b₀, E[b₀]ᵒᵖ → (Σ b₁, E[b₁] × Hom_B(b₀, b₁)ᵒᵖ) → Cat`

On a fibre object `e₁ ∈ E(b₁)` and a base arrow `b₀₁ : b₀ → b₁`, it
returns the fibre hom-category, where `(b₀₁)! e₀` is the
`E`-action/transport of `e₀` along `b₀₁`:
- `Homd_E(e₀, (e₁ , b₀₁)) ≔ Hom_{E(b₁)}( (b₀₁)! e₀ , e₁ )`

That is, this syntactic triangle/simplicial classifier `homd_`,
reduces to `globular` semantics, but is necessary for iterating
simplicially (triangles → tetrahedra → …) and for expressing
non-cartesian lax ω-functors and lax ω-transfors.

Moreover the functoriality of `Homd_E(e₀, (–,–))`, especially in its
second argument  `(Hom_B(b₀, –))ᵒᵖ`, espresses precisely the
“stacking” of 2-cells along a 1-cell (i.e. generalization of
horizontal composition of 2-cells meeting at a 0-cell).

    https://hotdocx.github.io/r/26043CPAL64002

This dependent comma/arrow/hom category `homd_` is analoguous to the
(directed) “bridge type” construction in the technique of logical
relations/parametricity, i.e. Ambrus Kaposi “Internal parametricity,
without an interval”; and it is really an *internalized*
type-theory/computational-logic as contrasted from Hugo Herbelin “A
parametricity-based formalization of semi-simplicial and semi-cubical
sets” which is merely a (formalized) combinatorial analysis.

## 2) Internalized computational-logic and “syntax elaboration”

The `emdash` Lambdapi specification looks like the categorical
semantics (“categories-with-families”) of a programming language; but
because it is carefully formulated to be “computational” and its
dependent-types/logic is “internalized”, then it can actually be
translated as a traditional programming-language/proof-assistant
surface syntax ( https://github.com/hotdocx/emdash ) whose HOAS
bidirectional type-checking and elaboration/engineering in TypeScript
is easily guaranteed.

For example, the fibred/displayed functor `FF : Functord_(Z) E D`
between isofibrations `E D : Catd Z` over `Z` is read as `z :^f Z, e
:^f E[z] ⊢ FF[e] : D[z]` (where binders `:^f` are functorial and `:^n`
are natural, and `:^o` is binding over objects-only). Thus `Functord`
is the traditional Π-type (`Functord_(Z) E D ≡ Π_(Z) (Functor_catd E
D)`), but with a construction `fapp1_funcd`, to express *lax*
functoriality in the `e : E[z]` variable (where `→_` is dependent hom
`homd_`, is used to express that this expression may be non-cartesian
in general, i.e. *lax* functor):
- `z :^f Z, e :^n E[z], z' :^f Z, f :^n z → z', e' :^n E[z'], σ :^f e
→_f e' ⊢ FF₁(σ) : FF[e] →_f FF[e']`

Similarly from the usual “diagonal” components `z :^f Z, e :^n E[z] ⊢
ϵ[e] : FF[e] → GG[e]` for a displayed transfor/transformation `ϵ :
Transfd_(Z) FF GG`, there is a construction `tapp1_fapp0` for
“off-diagonal” components (i.e. the index/subscript is an arrow
instead of an object), to express *lax* naturality/functoriality in
the `e : E[z]` variable:
- `ϵ :^f Transfd FF GG, z :^f Z, e :^n E[z], z' :^f Z, f :^n z → z',
e' :^n E[z'], σ :^f e →_f e' ⊢ ϵ_(σ) : FF[e] →_f GG[e']`

These constructions are expressed *internally* (as stable head symbols
`fdapp1_int_transfd` and `tdapp1_int_func_transfd`, etc... the
discharge/abstraction/lambda of the full (or partial) list of
variables in the context-patterns above), therefore those newly
introduced variables vary functorially/naturally. Note that when `E :
Functor Z Cat` is a module/profunctor, then the exchange of the order
of binder variables (i.e. “module-transport” vs “functor-action”) must
be an explicit operation:
- `z :^n Z, e :^f E[z], z' :^n Z, f :^f z → z' ⊢ (f)_!(e) ≔ E₁(f)(e) : E[z']`

And because there is available a “context-extension” / total-category
/ Sigma-category construction `Total_cat E : Cat` (a.k.a. `Σ_(B) E :
Cat`) for any fibred category `E : Catd B`, all these surface syntax
can actually happen within any ambient context `Γ, ⋯ ⊢` (i.e. the base
`Z` is itself `Total_cat Z0` for `Z0 : Catd Γ`). And the usual
categorical-logic fact that the Sigma/total-category `Σ b, –` is
left-adjoint to weakening/lift `–[b]`, means that the dependent
hom/arrow-category has an alternative formulation (`homd_curry` in the
lambdapi spec file `cartierSolution19.lp`):
- `Homd_E : Π b₀, E[b₀]ᵒᵖ → Π b₁, Hom_B(b₀, b₁)ᵒᵖ → E[b₁] → Cat[b₁]`

In reality, the *internal* computational-logic for lax ω-categories is
*easier* to express than for only strict 1-categories; because the
hom/comma of a category `Hom_D(y, F –)` (i.e. comma vs hom, is
necessary) is recursively a (fibred) category, and the arrow-action of
a *lax* functor `F₁ : Hom_C(x, –) → Hom_D(F₀ x, F –)` is recursively a
fibred functor which is non-cartesian (because of laxness), i.e. a
commuting-triangle/identity 2-arrow is mapped to a non-identity
2-arrow by `((F₁)₁)₀ : Homd_(Hom_C(x, –))(f, (g ∘ f, g)) →
Homd_(_)((F₁)₀ f, ((F₁)₀ (g ∘ f), (F₁)₀ g))`.

But for ω-iteration of the natural n-transfors construction (i.e
natural family rather than an individual n-arrow), there needs to be a
way to re-interpret a natural transformation again as a functor: this
is the question solved by the next section.

## 3) Naturality as “cut accumulation” and the exchange law

A (fibred) transformation: `F ⇒ G`, is also a transformation from the
unit/hom profunctor (i.e. “off-diagonal”): `hom(~, —) ⇒ hom(F ~, G
—)`, and is back again as a fibred functor between isofibrations: `∫
hom(~, —) → ∫ hom(F ~, G —)`; thus we can continue the ω-iteration of
this construction.

The key point is that *naturality can be oriented as an “accumulation”
rewrite* on these transfor's “off-diagonal” components `ϵ_(–)`
(cut-elimination style, where `⋅` is the vertical compositon/cut):
- `(G b) ⋅ ϵ_(a)   ↪  ϵ_(b⋅a)`
- `ϵ_(b) ⋅ (F a)   ↪  ϵ_(b⋅a)`

An instance of this accumulation rule is the *exchange law* between
horizontal and vertical compositions: an unambiguous “pasting diagram”
with two vertical 2-cells `α ≔ a` then `β ≔ b`, and one horizontal
2-cell `ϵ ≔ (e ∘ —)` for `e : f → g` (where `G ≔ (g ∘ —)` and `F ≔ (f
∘ —)` are horizontal post-composition/whiskering), will normalize to a
unique form (where `∘` is horizontal composition):
- `(g ∘ β) ⋅ (e ∘ α)   ↪  e ∘ (β⋅α)`

    https://hotdocx.github.io/r/26043CPAL65001

Moreover such formulations of naturality are useful to express
computationally the triangular identities of *adjoint functors*:
- `ϵ_(f) ∘ LAdj(η_(g))  ↪  f ∘ LAdj(g)`

and for sheaves and schemes, polynomial functors, higher inductive
types, etc... (ref: `cartierSolution16.lp`)

## 4) GPT-5.3-Codex diagrammatic prompting via `arrowgram` and “MathOps”

What is MathOps? Example: How to enable the GPT-5.3-Codex + Codex CLI
coding agent to (natively) understand and generate commutative
diagrams? A MathOps solution is: `arrowgram`
https://github.com/hotdocx/arrowgram/ an open-source strict JSON text
specification for commutative diagrams with exporting to
JSON/SVG/PNG/TikZ and with an AI-editor that generates and renders
`markdown` papers documents and slides presentations with embedded
diagrams specs, from any uploaded source references.

While the core `arrowgram` open-source app can be downloaded and used
offline, there is an academic-publishing overlay online SaaS app:
https://hotdocx.github.io to enable rapid/iterative MathOps from idea,
to sharing, to community peer review!

MathOps is what happens after you get “desk-rejected” by POPL 2026,
lol... A MathOps solution is the ability to share workspace sessions
(docker), with pre-installed running AI coding agents +
proof-checkers, for “vibe coding” live with co-workers, in a
marketplace where large-scale community-workspaces can get paid and
funded by fans and local businesses and governments; bypassing
well-known falsifications and intoxications.

This MathOps idea is implemented by
    https://GetPaidX.com — Publish and fund AI workspaces

backed by AI communities of 20,000+ developers in Dubai, Mumbai,
Shanghai https://meetup.com/dubai-ai https://meetup.com/mumbai-ai
https://meetup.com/shanghai-ai ... Try and experiment the AI workspace
for `emdash` here (e.g ask Codex “where is the dependent hom defined?
is it correct”):
https://GetPaidX.com/r/26044DLGJ77000


---

References:
[1] Kosta Dosen, Zoran Petric (1999). “Cut-Elimination in Categories”
[2] This summer visit to Ambrus Kaposi in Budapest, and `emdash`
discussions at RHPL@FSTTCS 2025 in India
[3] GPT-5.3-Codex

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