A few days ago I was watching a YouTube video on how terrible the writing and worldbuilding are in the latest Bethesda games, particularly in Fallout 4. Obviously I agree because they’ve gone steadily down since Morrowind, and good old Skyrim was likely the last thing they’ll ever do right. The YouTuber was going laboriously over all the incongruencies and canon breaks in the Fallout DLCs, particularly the Mechanist one; he argued that the introduction of raider-reprogrammed robots was a disaster canon-wise, because that means that regular settlements should have tons of robots tending to most menial tasks.

That got me thinking: why is worldbulding so hard? Is there a way to ensure that any canon addition never breaks existing canon? I told ChatGPT Pro to research in-depth regarding what narrative theory says about how to ensure worldbuilding is as robust as possible, and that every canon addition is evaluated against invariants and previously-established canon facts. Basically, every canon addition should propagate throughout the different aspects of the story world, and the invariants should either be preserved if they’re hard, or modified if they’re soft. Existing canon facts may need to be modified or reframed.

As I was analyzing ChatGPT’s report on the specific procedures and questions that world creation and every canon addition should ideally entail, which would take a human being way too long and too much brainpower, I thought that surely this can be formalized through AI. So I got Claude Code to the task.

In summary: worldbuilding and canon additions can absolutely be formalized, and the results are exceptional. I’ve ended up with several base files for the story world I’m working on (a fantasy one with sentient animal humanoids and in which magic is solely artifact-based, and the artifacts are like radioactive hazards). The AI maintains now the following base files: a canon ledger, economy and resources, everyday life, geography, institutions, invariants, magic or tech systems, mystery reserve, ontology, open questions, peoples and species, timeline, and world kernel.

Here’s the entire current content of the invariants markdown file, one of the shortest ones. Every CF-XXXX entry is a canon fact that I added and that Claude evaluated against the entire corpus.

---

# INVARIANTS — Animalia (note by me now: nevermind the name; it’s just an identifier)

World-level truths. New canon must not violate these without explicit user-approved revision.

—

## Ontological Invariants

### ONT-1 — Sentience requires biological embodiment

– **Statement**: All sentient peoples are biological, embodied beings with species-typical bodies, drives, lifespans, and senses. Sentience does not exist disembodied in this world. There are no ghosts who think, no walking gods, no machine minds.

– **Rationale**: Premise asks for low-magic, lived-in texture. Disembodied minds shatter the gritty frame and the species-as-civic-fact rule.

– **Examples**: a beaver-folk canal-master, an aurochs-folk wagon-driver, a human magistrate.

– **Non-examples**: ghosts who give orders, an AI ruling a city, a god walking the streets.

– **Break conditions**: only by explicit user-approved cosmological revision.

– **Revision difficulty**: high.

– <!– added by CF-0022 –> **Clarification (CH-0002)**: Modern crafted artifacts (CF-0021) sometimes behave as if “possessed” by entities with apparent agency. At the world level, these vessel-hosted agencies are NOT sentient; ONT-1 is preserved without exception. The in-world dispute about their nature (instructions / beastly / sentient) is observationally unresolvable and is tracked under Mystery Reserve M-6. The dispute does NOT cross-apply to animal-folk sentience (M-5 firewall).

– <!– added by CF-0029 –> **Extended Clarification (CH-0004)**: Magically-animated Maker-Age guardian constructions encountered in enterable ruins (CF-0029) similarly exhibit apparent autonomy without world-level sentience. ONT-1 is preserved without exception. The phenomenon is distinct in origin from modern-crafted vessel-hosted agencies (CF-0022) — Maker-Age guardian ≠ modern crafted apparent-agency — and the two are NOT to be conflated. Guardian-construction mechanism is tracked under Mystery Reserve M-8; presence-heterogeneity (why some ruins have guardians and some don’t) under M-10. The M-5 firewall against animal-folk sentience cross-application applies equally here.

– <!– added by CF-0035 –> **Fourth Clarification (CH-0009)**: Artifact-contaminated mutated non-sentient beasts (CF-0035) in wilderness-distal sites remain categorically NON-SENTIENT. Artifact exposure does NOT produce sentience, speech, tool-use, or proto-folk status in a non-sentient host — morphological and capability alteration is not a step toward sentience. ONT-1 is preserved without exception; the M-5 firewall against cross-application to animal-folk sentience holds for the fourth time (after CF-0022, CF-0029, CF-0031). Mutated-beast phenomenon is DISTINCT in origin from both modern-crafted vessel-hosted agencies (CF-0022) and Maker-Age guardian constructions (CF-0029) — three surface-similar Maker-origin phenomena must NOT be conflated; each has its own bounded-unknown mechanism surface (M-6 / M-8 / new M-15 for the gargantuan-underground scale-tail).

### ONT-2 — Magic exists only as artifact, not as learnable art

– **Statement**: Living people cannot cast spells from will alone. Magical effects are produced by physical artifacts — ceramic, wood, metal vessels and devices — predominantly made by lost makers, with a marginal modern stream produced by leaked-grimoire crafter attempts (CF-0021). Some can be used; some can only be contained; many do nothing recognizable until they fail.

– **Rationale**: Premise. Forces the magic-as-hazard texture and prevents the world drifting into hereditary-mage high fantasy.

– **Examples**: ceramic containment vessel for extracting corruption; an artifact that mind-controls animals into wading water; a modern crafter’s wood-vessel that hums and once destroyed three village hens before going inert.

– **Non-examples**: a wizard throwing fire from his hands; a hereditary mage bloodline; a learned spell.

– **Break conditions**: only by explicit user revision.

– **Revision difficulty**: high.

– <!– added by CF-0021 –> **Annotation (CH-0002)**: The “made by lost makers” clause now includes a marginal modern reverse-engineering. The artifact-as-mediator constraint holds — what is learned by crafters is the craft of producing vessels, not the channeling of magic through the practitioner. The magic still lives in the artifact, not in the maker.

– <!– added by CF-0039 –> **Destruction-Physics Clarification (CH-0014)**: The artifact-as-locus clause carries material-physical consequence: the binding of magical effect to the vessel in Maker-Age artifacts (CF-0039) confers destruction-resistance on the vessel itself — destruction-attempts BIND the effect more deeply rather than unmaking it, and the vessel’s material resistance is elevated accordingly. This is a property OF the artifact-as-locus, NOT a new channel through the crafter. The destruction-physics is SCOPED to Maker-Age artifacts; modern crafter outputs (CF-0021) remain destructible by ordinary means, which preserves CF-0021’s “inferior” stabilizer register. ONT-2 holds without exception.

### ONT-3 — Species do not interbreed

– **Statement**: A hyena-folk and a human cannot produce a child. Cross-species sexual relationships exist socially but are reproductively sterile. Family across species is built through marriage, fostering, and adoption — not blood.

– **Rationale**: Without this rule, speciation collapses, embodiment loses meaning, and “halfbreed” plot conveniences erode the social texture. (Logged for OPEN_QUESTIONS as user-revisable.)

– **Examples**: cross-species marriage with adopted heirs; a human noble and a fox-folk consort raising a fostered hare-folk child.

– **Non-examples**: hybrid offspring, “half-cat half-human” characters.

– **Break conditions**: requires user approval; would force redesign of kinship, succession law, and species cohesion.

– **Revision difficulty**: high.

– <!– added by CF-0035 –> **Clarification (CH-0009)**: “Chimeric” morphology observed in artifact-contaminated mutated non-sentient beasts (CF-0035) — fused features, parallel limbs, merged apparent anatomy — is ARTIFACT-EFFECT on an already-contaminated individual organism, NOT cross-species reproductive hybridization. Species reproductive boundaries are preserved: no mutated-beast lineage arises from sexual interbreeding across species. The chimeric register applies to the shaped-by-artifact body, not to the reproductive act. ONT-3 holds without exception.

—

## Causal Invariants

### CAU-1 — Artifact effects always cost

– **Statement**: Every effect drawn from a magical artifact costs the user, the host, the environment, or all three. Costs include fatigue, host trauma, ward attrition, environmental “bleed-through” (dimming light, gloom, animal compulsion), and slow contamination of place.

– **Rationale**: Brief specifies the ceramic containment procedure is brutal to the host and that artifacts can corrupt water and mind-control beasts.

– **Examples**: extraction leaving the host bedridden; ward attrition near a contained artifact; canal water gone “wrong” downriver of a buried device.

– **Non-examples**: a free, clean magical effect; a costless ward.

– **Break conditions**: forbidden — would invalidate the artifact-as-hazard frame.

– **Revision difficulty**: high.

– <!– added by CF-0035 –> **Cost-Taxonomy Extension (CH-0009)**: The cost taxonomy includes a **rare survival-as-mutation outcome** observed in non-sentient fauna (CF-0035) exposed to uncontained artifacts over time in wilderness-distal sites. Most beasts die of artifact exposure (ordinary CAU-1 lethality); a rare subset survive and exhibit morphological and capability alteration. Survival does NOT exempt the environment, the local ecology, or subsequent secondary hosts from cost; the rare “beneficial for the beast in its niche” outcome (dangerous predator status) is an individual-level windfall embedded in a population-level cost catastrophe (most died). Cost universality holds without exception.

– <!– added by CF-0039 –> **Cost-Taxonomy Extension (CH-0014) — destruction-attempt cost-transfer**: The cost taxonomy includes **destruction-attempt cost-transfer** as a variant form observed on Maker-Age artifacts (CF-0039). Attempts to destroy a Maker-Age artifact — by smithing, fire, crushing, dissolution, or other means available to current-age capability — do NOT annihilate the magical effect; the attempt instead BINDS the effect more deeply into the vessel, elevating the material resistance of the substrate (wood hardens to behave like strong metal; ceramic sets harder; metal refuses the hammer). The cost manifests partially as a material-elevation cost on the vessel (transformation into higher-order resistance) and partially as an attempt-cost on the attempting party (injury, exhaustion, equipment loss, ward-attrition radius). The cost-universality principle holds without exception — destruction-attempts do not escape cost; they redirect it. Cost universality holds without exception. Also see CF-0041 sealed-inert extension: opening a sealed Maker container ACTIVATES the artifact within with CAU-1 cost, making unknown-container unsealing a feared cultural moment.

– <!– added by CF-0040 –> **Cost-Taxonomy Reaffirmation (CH-0014) — mundane-tier per-artifact contamination**: CF-0040 commits that mundane-tier Maker-Age artifacts (breeze-dolls, tick-mirrors, weak coin-sorters, scar-rubbers) are commonly found in ordinary-life contexts; the CAU-1 principle still holds without exception for this tier. Every mundane-tier artifact carries a cost surface — slow-bleed on user, room-misfeel, animal unease, household water off-flavor, vessel fatigue across months of proximity. No “harmless charm” reading is world-truth; the low-tier artifact is low-tier COST not no-cost. AES-3 contamination-clause compliance is mandatory for every mundane-tier CF-record annotation.

### CAU-2 — Corruption produces diagnostic environmental and behavioral signals

– **Statement**: Bleed-through gloom, dimming light, objects feeling “wrong,” compulsions in animals or people are diagnostic of nearby uncontained artifact activity. Practitioners (and seasoned canal-folk) read these signals.

– **Rationale**: Brief specifies bleed-through symptoms used as diagnostic by practitioners.

– **Examples**: a canal-side beaver-folk noticing fish behaving strangely and calling for an inspector; a ward-wright walking the perimeter and feeling the air thin.

– **Non-examples**: invisible, undetectable magical contamination.

– **Break conditions**: forbidden.

– **Revision difficulty**: high.

### CAU-3 — Wards are a public-but-restricted social-technical system

– **Statement**: Wards are publicly understood as a containment system. Their existence, locations, and the concept of “ward breach” are common knowledge. Their specifics — the inscriptions, the materials, the maintenance schedules — are restricted speech, regulated by guild charter.

– **Rationale**: Brief specifies ward-breach as known, and that public discussion of wards carries social risk.

– **Examples**: a child knows what a ward marker looks like; an apprentice cannot legally describe the inscription pattern aloud in a tavern.

– **Non-examples**: wards as secret unknowable magic; wards as fully open public technology.

– **Break conditions**: forbidden.

– **Revision difficulty**: medium.

—

## Distribution Invariants

<!– added by CF-0040 –> ### DIS-1-EXT (CH-0014) — Mundane-tier is explicit subset of “most inert junk” band, not a new distribution tier

CF-0040 commits the mundane-tier (near-imperceptible-effect artifacts: breeze-dolls, tick-mirrors, weak coin-sorters, scar-rubbers) as an EXPLICIT naming of the LARGEST share of the DIS-1 “most inert junk” band, reframed: most of what DIS-1 described as “inert” is in fact LOW-TIER ACTIVE, carrying per-artifact CAU-1 contamination clauses. Inverse strength-rarity relationship holds across the artifact corpus: mundane-tier is the most common; catastrophic-class is the rarest. The mundane-tier IS a subset within DIS-1, NOT a new distribution tier at the distribution-invariant level.

### DIS-1 — Artifacts are routinely turned up underground

– **Statement**: Foundations, canal-digging, mining, and ruin-clearance regularly turn up artifacts. Most are inert junk. A small fraction are dangerous. A tiny fraction are catastrophic.

– **Rationale**: Brief specifies routine construction can unearth them.

– **Examples**: a beaver-folk canal-crew finding a ceramic shard that registers as inert; a foundation dig that uncovers a humming metal disc and triggers a quarter-town evacuation.

– **Non-examples**: artifacts as so rare no one has ever seen one; artifacts as so common they fill marketplaces.

– **Break conditions**: would change the entire artifact economy.

– **Revision difficulty**: medium.

– <!– added by CF-0027 –> **Cross-reference (CH-0004)**: Enterable Maker-Age ruin sites (CF-0027) are a recognized subset of Maker substructures that admits organized multi-professional entry; piecemeal unearthing per DIS-1 remains the dominant modality, but enterable-ruin expeditions (CF-0028) are the less-common, high-risk, high-yield variant. The DIS-1 distribution pattern (most inert, small fraction dangerous, tiny fraction catastrophic) applies equally to enterable-ruin recoveries; catastrophic-class finds trigger resealing rather than recovery (preserves Mystery Reserve M-2).

– <!– added by CF-0035 –> **Wilderness-Distal Subset (CH-0009)**: A subset of DIS-1 unearthings occurs in wilderness beyond civic / guild / chartered-watch reach (earthquake-exposed, flood-exposed, burrowing-animal-exposed, slow-soil-creep-exposed). These exposures are not detected by inspectors and not contained by chartered response; the artifacts remain active in place. Over time this subset produces the CF-0035 contaminated-fauna phenomenon. Inspector-dispatch to wilderness-distal sites is DISCRETIONARY (gated by patron-funder or estate-commission or declared civic-watch predicate), not mandatory — cost, escort requirement, and wilderness reach preclude routine extension. DIS-1 distribution pattern holds within the wilderness-distal subset as everywhere else.

### DIS-2 — Literacy and occult-fragment access is partial, not aristocratic monopoly

– **Statement**: Literacy is not universal but is not gated to nobility. Occult text fragments can be purchased by anyone with coin and a willing seller. Specialist knowledge is gated by guild and apprenticeship more than by class.

– **Rationale**: Brief specifies fragment purchase is possible.

– **Examples**: a tavern bard who can read trade-tongue; a journeyman extractor who owns three fragments; a literate canal-master.

– **Non-examples**: only nobles can read; only priests own books.

– **Break conditions**: would change the structure of knowledge access.

– **Revision difficulty**: medium.

### DIS-3 — Mythical-species sentients are population-rare and locally clustered

– **Statement**: Mythic-species sentients (basilisk-folk, chimera-folk, manticore-folk, gryphon-folk, naga-folk, etc.) exist among animal-folk but are population-rare per region. You do not see a chimera in every market.

– **Rationale**: Prevents specialness inflation. Preserves wonder. Matches the brief’s note that exotic-species bodies attract attention and commentary in public.

– **Examples**: a single naga-folk bargemaster known by reputation across a canal corridor; a basilisk-folk physician practicing in only one city.

– **Non-examples**: mythic species as common as cat-folk.

– **Break conditions**: would inflate mythic-species into background-noise.

– **Revision difficulty**: medium.

– <!– added by CF-0035 –> **Firewall (CH-0009)**: Artifact-contaminated mutated non-sentient beasts (CF-0035) are CATEGORICALLY DISTINCT from Cluster D mythic-species sentient folk. The surface similarity (unusual morphology; chimeric features; wonder-adjacent register) must NOT be conflated: mutated beasts are non-sentient fauna with artifact-shaped bodies; mythic-species sentient folk are civic-participant peoples with species-typical embodiment (ONT-1/SOC-1). The firewall holds across all encounter contexts — no in-world institution may process a mutated beast as a mythic-species individual, and no mythic-species individual may be treated as a mutated-beast specimen.

—

## Social Invariants

### SOC-1 — Animal-folk can occupy any class

– **Statement**: Class mobility is not species-coded. Animal-folk can hold landed nobility, civic authority, guild mastery, and craft livelihoods. A beaver-folk magistrate and a human laborer are both ordinary.

– **Rationale**: Brief explicit.

– **Examples**: an aurochs-folk landowning estate that employs human and otter-folk laborers; a hyena-folk magistrate presiding over a mixed-species court.

– **Non-examples**: caste systems where humans rule and animal-folk serve; species-coded slavery.

– **Break conditions**: forbidden.

– **Revision difficulty**: high.

– <!– added by CF-0036 –> **Clarification (CH-0010)**: individual and sectarian species-prejudice exist as ordinary sociological phenomena (tavern slurs, labor-prejudice distancing, crew-composition sorting preferences, marriage-broker catechism extensions). Isolated single-species exclusionary settlements exist in weak-charter / demographically-fragile regions. Supremacist sectarian doctrine asserting species entitlement to violence against other sentient peoples exists as CONTESTED-CANON sectarian belief held by a fringe. An interspecies-cannibal sub-subset exists within CF-0034 outlaw bands. **None of these constitute world-level class-coded species hierarchy.** Civic charters continue to suppress hierarchy-speech at world level; no chartered polity adopts supremacist doctrine as civic policy; no guild charter gates intake by species; no magistrate-court recognizes a “lesser sentient” legal category. SOC-1 holds without exception. Individual-and-sectarian friction ≠ civic hierarchy; the former is ordinary social phenomenon, the latter is the forbidden break-condition.

### SOC-2 — Public adult barter is legal and visible in many regions

– **Statement**: Sexual services can be publicly posted, framed as pragmatic exchange, and treated by many locals as mundane. Scandal attaches to the character of those involved, not to the act itself. Regional and class variation exists.

– **Rationale**: Brief explicit.

– **Examples**: a posted price-list at a tavern; a respectable courtesan whose patrons include guild-masters; quiet disapproval from a stricter sectarian household.

– **Non-examples**: blanket criminalization; blanket destigmatization.

– **Break conditions**: would shift the texture significantly; medium revision difficulty.

– **Revision difficulty**: medium.

### SOC-3 — Coin contract is sacred by custom

– **Statement**: A payment contracted in coin or in-kind must be honored, or restitution made. Breach is a recognized civil and customary wrong; reputation damage compounds the legal cost. Trade across species depends on this norm.

– **Rationale**: Derived from the brief’s coin-and-livestock framing; necessary for stable trade across species and regions.

– **Examples**: a tavernkeeper hounding a defaulted patron through three towns; a guild withholding work from a known oath-breaker.

– **Non-examples**: payments routinely renegotiated after delivery without consequence.

– **Break conditions**: low — story tension often arises from breach.

– **Revision difficulty**: low.

### SOC-4 — Artifact extraction and traffic is guild-licensed

– **Statement**: Extractors, containment-wrights, and artifact-brokers operate under chartered guilds in most polities. Unlicensed possession of magical artifacts carries criminal or civil penalties. Black markets exist but operate at risk.

– **Rationale**: Derived from brief’s “professions and guilds exist to extract … research … sell … to bidders” plus the social risk around ward discussion.

– **Examples**: a guild-stamped artifact in a noble’s collection; a smuggler executed for trafficking an unregistered device.

– **Non-examples**: anyone can dig and sell freely.

– **Break conditions**: medium.

– **Revision difficulty**: medium.

—

## Aesthetic / Thematic Invariants

### AES-1 — Heroism is paid in coin and scars, not glory

– **Statement**: Risk-taking is treated as labor. Veterans are quietly proud and dryly mocking of glory-talk. Songs that romanticize battle exist but are sung mostly by those who never fought.

– **Rationale**: Tonal contract. The “scarred veteran with longsword” framing of the brief.

– **Examples**: a pension-list at a guildhall; a tavern song that ends with an unpaid widow.

– **Non-examples**: chosen-one narratives treated as world-truth.

– **Break conditions**: would betray tone.

– **Revision difficulty**: high.

### AES-2 — The ordinary keeps the world honest

– **Statement**: Daily life — canal traffic, livestock, tavern songs, winter dread, child-rearing — is always present in the texture. The world cannot be experienced solely from the perspective of heroes, nobles, or cosmologists.

– **Rationale**: Skill discipline; brief emphasis on lived realism.

– **Examples**: a story whose stakes are framed in terms of who eats this winter; a battle scene whose aftermath shows the field being looted by tenants.

– **Non-examples**: a world rendered only as cosmology and ruling families.

– **Break conditions**: would betray world identity.

– **Revision difficulty**: high.

### AES-3 — The magical and the contaminated are aesthetically allied

– **Statement**: Wonder and dread are inseparable in this world. Magic is never simply pretty. Every magical experience carries contamination — physical, social, or moral.

– **Rationale**: Brief.

– **Examples**: an artifact that is beautiful and lethal in the same breath; a containment-wright respected and quietly avoided. <!– added by CF-0035 –> A six-limbed boar carcass hauled to a ward-inspector’s door — the hunters dryly proud, the villagers quietly moving the children indoors; the trophy hung in a guildhall smoke-room, not paraded.

– **Non-examples**: charming, harmless magical decor.

– **Break conditions**: forbidden.

– **Revision difficulty**: high.

---

I used to hate worldbuilding, but this method makes it fun, as well as a solved problem. This is basically programming-as-prose. It’s already revolutionizing many industries.