Assignment-aware football simulation

Your install, run a thousand times before Sunday.

Most analytics grade football without ever reading a playbook. They can tell you what happened. They can't tell you whose job broke, or what beats the look you're getting Sunday. Gameplay.AI starts from your book. Your progressions, your alerts, your assignments. Every number comes back with a why.

Built for the complexity of an NFL install book and the volume of a college season.

dropback · dagger · gun doubles · 11 personnelvs Cover 3
The dagger concept from gun doubles, 11 personnel, against Cover 3A coaching diagram. Five receivers run routes from the line of scrimmage against a Cover 3 shell drawn as three deep defenders and four underneath. Z runs a 15-yard dig and is read one — the concept's answer — breaking inside into the window between the underneath hook defenders and the deep middle safety. Y runs a 22-yard seam, read two; it is the concept's clearout, and its job is to carry the free safety out of the middle rather than to receive the ball. X runs a 25-yard go on the back side, read three, holding the backside deep-third corner. TE runs a 5-yard drag, read four. HB runs a 3-yard checkdown, read five.5101520CBFSCBNBWMSSZYXTEHB
Authored progression
  1. 1Z dig15yd
  2. 2Y seam22yd
  3. 3X go25yd
  4. 4TE drag5yd
  5. 5HB checkdown3yd

A canonical library play, built from first principles. Plays extracted from an install book additionally carry the page and line they came from.

Y's seam is the clearout — its job is to occupy the free safety in the deep middle, not to catch the ball. The dig breaks underneath him, into the window between the hook defenders and the deep middle, which is why the dig is read one. X's go holds the backside corner and is the late answer if the middle gets taken away. Knowing which route is the answer and which one is doing the clearing is the difference between simulating football and simulating receivers.

01 · Your playbook

A league average has never told a coach what to call.

Generic tools grade everybody's film with nobody's playbook. The best they can hand you is a tendency. But the things you control — the call, the protection, the read — live in your book. So that's where we start. Your install gets read in first, page by page, and everything downstream speaks its language.

What the stat sheet sees

2nd & 7 · 11 personnel

Checkdown. Gain of 4.

Behind schedule.

Grade: below expectation.

With your book open

Dagger into Cover 3, and the Mike sat on the dig — so the answer was never open. The seam carried the free safety, like it's supposed to. Your quarterback got off it and took the outlet on time. That's not a broken play. That's a Mike who played the dig right — and dagger's answer for that is the outlet, exactly where the ball went. The readout says so. The fix is a check, not a benching.

One of these you can coach on Wednesday.

474

plays read in from real install books

416 offense · 58 defense · 246 validator-confirmed

466

cite the exact page and line they came from

98% source-traceable

195

formations in the football vocabulary

plus 27 fronts and 23 protections

10

coverages modelled as per-defender jobs

5 of them with match conversion

Your words

When your book says Buzz, that's a named call in the system — Buzz, Cloud, Rip/Liz, carried as the calls they are, not flattened into one generic label. What your staff means by a call survives from the film tag to the sim.

Your progressions

A play isn't a route tree. It's a set of assignments that beat a structure. The engine holds the protection, the progression, and the alert — so it knows which route was the answer and which one was there to move a defender.

Your adjustments

Strength declarations, motion bumps, backside alerts. If the install changes on Wednesday, the model changes with it, instead of drifting back to what the league does on average.

Extraction counts are from the current corpus — Bruce Arians' 2016 Cardinals, Greg Roman's 2014 49ers, and Nick Saban's 2008 Alabama defense — used to build and prove the pipeline. Your book stays yours; see below.

02 · The loop

The tape teaches the sim. The sim sharpens the plan.

One system, one language — the one your playbook defined. Film in, tags confirmed, model updated, plan tested. Nothing gets lost in an export on the way to the call sheet, and every pass through the loop makes the model sound more like your team.

  1. 01

    Your book

    Read in once, page and line cited. It defines the language everything else speaks.

  2. 02

    Film

    The tape comes in Sunday night. Cut-ups, angles, and plays land in one place.

  3. 03

    Tags

    Your staff tags coverage, front, motion, and concept in your own terms — vision assists, and a coach confirms every tag before it counts.

  4. 04

    Priors

    Confirmed tags become what the model expects — from your guys and from theirs. Team-private. Never pooled with anyone else's.

  5. 05

    The sim

    Run Tuesday's plan into the defense you're actually getting. Their rules, not the league's.

  6. 06

    The call sheet

    What survives goes to Sunday. And Sunday's tape starts the loop again.

  7. …and back to the film. That's why it's a loop and not a pipeline.

Your data stays yours. Team-private film and tags drive your model only. They're never pooled into a shared or public model — that separation is built into the schema, not promised in a policy.

03 · The sim

You can't grade the play without knowing the assignment.

Thousands of reps per call. Every defender has a job, every read has an order, and the output isn't just a distribution — it's the reason behind it, in the language you'd use in the install meeting.

Defenders have jobs

Who carries the seam. Who squats the flat. Who's got the back out of the backfield. Outcomes come from those jobs colliding with your routes, not from a lookup table.

The QB plays the position

He works it one-two-three, comes off a covered read, stays on an open one, and takes the checkdown when the field's covered. Because that's the job.

Answers and decoys

A clearout's job is to move a defender, not to catch the ball — unless the defender won't go with it. The engine knows the difference, and it knows the alert that flips it.

The sticks are part of the call

Down, distance, field zone, clock. A third-and-two model that ignores the sticks is a yards model wearing a football jersey.

When a rep dies in the sim, the readout names the job that broke — the hook that sat on the dig, the rub that never came free. That's fault you can coach, not a grade you have to argue with.

53plays in the simulation library
8play families, run through pass
10coverages with per-defender rules
1,689engine tests on every change

04 · Trust

A coach's first question is “says who?”

Any model can produce a confident number. Staffs stop trusting analytics when the number can't be traced, argued with, or checked against the tape.

So traceability is enforced in the build, not left to discipline. If a claim can't show its footing, it doesn't ship. And when the evidence is thin, the surface says so out loud.

The engine's outputs are held against three seasons of public play-by-play, and the run game is asserted to within half a yard per carry of it, gap by gap and box count by box count. It's checked against the league — which isn't the same thing as being the league, and we won't tell you otherwise.

457 numbers, 457 citations

Every value the model relies on has to declare where it came from before it can ship, and a test fails the build if one doesn't. Made-up constants aren't a matter of taste here. They break the build.

Thin evidence says so

When a rate rests on eleven plays, it says so and shows its denominator. We'd rather hand you a number with its footing than a confident-looking average.

The football gets checked too

Every classification is validated against canonical coaching material before it ships. A mechanism that reads well but isn't how the coverage actually works doesn't make it in.

05 · The road

The sim is the first piece, not the whole idea.

Everything above this line is live today. Here's where the loop goes next — each piece built on the same foundation: your book, your language, your data.

In build

Film that tags itself

Upload Sunday's tape and the tags draft themselves — in your terminology, against your book. The chain is proven on real NFL All-22: 22 of 22 plays machine-tagged with no hand-holding, zero contradictions with the official play-by-play. Productizing that pipeline is the current build. The coach-confirm gate stays; trust isn't a feature we'd trade for speed.

Next

Grades that know the assignment

Outcome grades tell you what happened. Assignment grades tell you who to coach. Because the system holds your install, it can grade a player against the job your book gave him — the fit he had, the man he was supposed to carry — starting with your own roster, where you can verify every call.

Next

From game plan to practice script

The same loop that finds the tendency should write the period that fixes it. Film to tags to sim to Wednesday's practice plan, without the meaning changing hands.

Bring your book. We'll show you what it does against the look you're getting Sunday.

We're taking a small number of NFL and NCAA staffs for early pilots. One game and one defense to start. You keep everything that comes out of it.

Or write to clarence@gameplaytech.ai.