The local machine
48 plates, 18 sprites
Plates from 10:24 to 11:55 and sprites from 11:04 to 12:24, each cut into layers for the theatre. The voice lines took about a minute of CPU time at 10:49.
Real-time film · 9:11 · production notes · 17 October 2026
Footfall
A nine-minute film that follows one unbroken trail of tracks from a worm-burrow on a Precambrian seabed to bootprints on the Moon and rover treads on Mars, told as light shining up through a black stage floor in coloured shadow theatre. Nineteen agents built it in under three hours. This is where the time and the money went.
The session in four numbers
From a request to a published film
2 h 45 minfrom the request at 10:10 to the commit at 12:54
14 h 29 minof agent working time, run in parallel
19 agentsone Opus director, 14 Sonnet and 4 Haiku agents
$148.37if every call had been billed at API list prices
9:11 film1920×1080 at 3045 shots50 lines, 1,430 words1 voice48 plates18 sprites1,351 sound cues11,600 lines of film code
The afternoon
10:10 to 12:54
Each bar is one agent, from its first instruction to its last report; each thin mark is a tool call. The three local rows mark every picture, sprite and voice line the machine produced. The four researchers went first, the director ran the pilot and wrote the script, the engine builders came next, and eleven chapter animators worked in one wave.
Opus 5.5Sonnet 5.5Haiku 5.5Local machine, no API cost
The company
Who did what, for how long, at what price
| Agent and assignment | Ran (local) | Time | API calls | Tool calls | Cost at list prices |
|---|---|---|---|---|---|
| Director · Opus 5.5 | |||||
| Director: orchestration, review and export | 10:10–12:54 | 2 h 45 min | 288 | 400 | $46.14 |
| Research · Haiku 5.5 | |||||
| Research deep time tracks | 10:18–10:21 | 2 min | 14 | 31 | $0.04 |
| Research industry, space, computing | 10:18–10:21 | 2 min | 9 | 17 | $0.03 |
| Research civilisations and exploration | 10:18–10:20 | 2 min | 11 | 26 | $0.02 |
| Research human origins migration | 10:18–10:21 | 3 min | 6 | 16 | $0.05 |
| Engines · Sonnet 5.5 | |||||
| Puppet engine: human rigs | 10:50–11:15 | 25 min | 68 | 95 | $3.04 |
| Sprite rig engine | 10:50–12:33 | 1 h 42 min | 304 | 400 | $19.19 |
| Score · Sonnet 5.5 | |||||
| Composer: YuE2 score | 11:23–12:41 | 1 h 18 min | 158 | 163 | $7.15 |
| Animation, one agent per chapter · Sonnet 5.5 | |||||
| Animator c01 First trails | 11:26–12:00 | 34 min | 85 | 129 | $4.66 |
| Animator c10 Invisible trail | 11:23–12:15 | 52 min | 104 | 137 | $6.63 |
| Animator c09 Leaving | 11:35–12:26 | 50 min | 130 | 160 | $8.75 |
| Animator c11 Next (shots 1-3) | 11:35–12:08 | 32 min | 99 | 116 | $4.91 |
| Animator c07 Over the horizon | 11:35–12:14 | 39 min | 86 | 102 | $4.92 |
| Animator c03 Giants | 11:35–12:13 | 37 min | 97 | 140 | $5.34 |
| Animator c08 Iron | 11:35–12:38 | 1 h 02 min | 167 | 213 | $9.52 |
| Animator c02 Onto land | 11:35–12:16 | 40 min | 119 | 146 | $6.02 |
| Animator c06 Settling | 11:35–12:26 | 50 min | 151 | 183 | $8.30 |
| Animator c04 Upright | 11:23–12:00 | 37 min | 116 | 143 | $5.95 |
| Animator c05 Spreading out | 11:35–12:29 | 54 min | 136 | 161 | $7.69 |
| 19 agents | 2,148 | 2,778 | $148.37 | ||
The bill
Where $148.37 went
By role
Director · $46.14 · 31%Pitch, pilot, script, review of every chapter at full size, export and publishing.
4 Haiku researchers · $0.14 · 0.1%Short research notes, capped at ten minutes and twelve fetches each.
2 engine builders · $22.24 · 15%Jointed human puppets, and sprite rigs with planted feet.
Composer · $7.15 · 5%Wrote its own ABC scores for YuE2 and aligned the renders.
11 chapter animators · $72.71 · 49%Eleven Sonnet agents in one wave.
By model
By kind of token
The director, hour by hour
Each gap between two transcript events is given to the tool call or message that ended it, then sorted by tool name, file path and command. The buckets are keyword matches, so read them as proportions. 2 h 45 min in all.
The animators
How long each chapter took
Every chapter was reviewed at full size and sent one or two polish rounds.
Eleven chapters, one animator each
The film
What the afternoon produced
One voice
50 lines
1,430 words read by bm_fable at speed 0.95, as you chose. You heard and approved the opening audio at 11:46 (“sounds good, nice mix”); the rest of the mix was measured only.
The score
YuE2, arranged
The composer wrote its own ABC scores for YuE2, whose planner ignores key and tempo, and aligned the renders with chroma DTW and a time-stretch. Footfall percussion comes from the step events.
The MP4
9:11, 232 MB
1920 by 1080 at 30 fps, exported in parallel chunks, with a 28.7 MB single-file page and a 540p share copy. The browser scan drew 552 frames, one per second, with no console errors.
What the checks caught
Eleven findings and what was done
The review log records the pilot draft’s faults as found, and the recurring problems the director briefed up front for the later chapters.
| Found | What went wrong | How it was handled |
|---|---|---|
| Pilot draft: staging | The horizon sat about 100 px above the ground line, so the walkers’ legs vanished against a dark plain | Plates rescaled so the walkers stand against the lit hills |
| Pilot draft: the figure | A rectangular torso slab, arms lost inside the silhouette, a boxy hood, a crude fur fringe and joint pins that read as dust | Puppet rebuilt on a test bench, with slimmer torso, separated limbs and pins removed |
| Pilot draft: the prints | Hominin prints read as tadpoles, and older tracks were as bright as the hero trail, a dotted highway | Prints redrawn as heel, arch, ball and five toes; older tracks dimmed so the fresh trail leads |
| Pilot draft: the card | A hard white bar where the light leaked over the card edge, and black grass invisible on black | The light confined to the card; tall grass rising into the light |
| Smoke and clouds | A cartoon chain of circles | Every later brief asked for one-fill scalloped lace-cut lobes |
| Generated people | They lose limbs | People drawn as code puppets |
| Glowing slab | Read as a modern tablet computer | Redrawn |
| Labels | Pushed off the bottom of the frame | Repositioned in review |
| Weak sprites | The Voyager and the first-pass horse were weak | Better sprites generated, and the galloping horse rebuilt as a rigged sprite |
| Smoke test | Reported an error | A fault in the Node test harness; a browser scan of 552 frames was clean |
| Left open | A theropod hip notch, roundish launch smoke, a grass blade crossing the “Rainhill, 1829” label, and a horse that only tosses its head instead of looking back | Accepted as minor and listed in the notes |
What it taught
Six things the numbers say
Research was nearly free
Four Haiku researchers cost $0.14 in all, 0.1% of the bill, and each finished in 2 min to 3 min, because the brief capped them at ten minutes and twelve fetches.
A pilot and two enhancement passes came first
The Laetoli pilot was inspected, rebuilt and re-lit twice on the real code path before anything was scaled. The review log records the draft’s faults honestly, and you approved the pilot at 10:44.
Engines first, then eleven animators in one wave
The two engine builders cost $22.24, and the sprite-rig engine alone was the dearest subagent at $19.19. The eleven animators then started together between 11:23 and 11:35, cost $72.71 (49%) and ran 32 min to 1 h 02 min.
The director waited more than it did anything else
1 h 13 min of the director’s 2 h 45 min went on waiting for agents, and the last chapter, c08 Iron, took 1 h 02 min.
One Opus agent cost nearly a third
The Opus director cost $46.14, 31% of $148.37, and the fourteen Sonnet agents $102.10. The film cost $16.16 per finished minute.
The sound cues came from the picture
The 1,351 sound events were timed by the same code that draws each picture event. The composer was asked to thin the densest chapter, about 180 locomotive chuffs and 100 rail clicks in under a minute, so they never crowd the music.
Method
How these figures were measured
Measured from the session's own transcripts: the director's, and one for each of the 18 agents it launched. Assistant messages are deduplicated by message id and the last entry's usage is kept. Models come from each agent's metadata. Figures run to the commit at 12:54.
Cost is what the usage would have cost at API list prices in October 2026: Opus 5.5 at $4 per million input tokens and $20 per million output, Sonnet 5.5 at $2 and $10, Haiku 5.5 at $0.10 and $0.50 (higher rates above a 100,000-token prompt), cache reads at 0.05 times input, cache writes at 1.25 times (five minutes) or 2 times (one hour). A subscription session was not billed this way, so treat the dollar figures as a measure of work, not an invoice.
Times are UK local time (BST, UTC+1). Local-machine marks are the modification times of the generated files. The pilot findings come from the project’s review log and the open items from the director’s notes. The file sizes and dates come from the project files. The hour-by-hour split sorts tool calls by keyword, and gaps of more than 20 minutes with no events are left out of it.