SCP Tagging Guide

For a more general guide to tagging pages, see the A Laymen's Guide to Tagging.
This guide specifically focuses on the tags that can only be applied to SCP Articles: Object Classes and Attributes.

This guide is intended for use by both authors and members of the tagging team, as well as by people considering becoming members of the tagging team who would like to understand what it involves. If you do not feel confident, do not tag your own articles, and leave it to the tagging team. However, if you would like to help us out and get your article tagged more quickly, please make use of this guide to correctly tag your own articles. You are also welcome to apply Genre Tags to articles, as explained in this guide.

While authors are free to tag their own articles, if they are unsure how to tag an article, they are free to leave it untagged or only partially tagged, as long as they do not apply the scp tag. Applying the scp tag to an incompletely or incorrectly tagged article is a tagging infraction, and so is applying any tag not listed on the Tag List, so please check that you've spelled them all correctly and haven't imagined the existence of tags that aren't actually there. Site members who tag incorrectly will be warned at first, but repeated tagging infractions will mean that you will no longer be permitted to tag articles, and will face disciplinary action if you continue to do so, such as the revocation of your site membership.

Articles eligible for Object Class and Attribute Tags

All SCP articles, including main series articles (SCP-XXXX), Proposals for SCP-001 (tagged 001-proposal), translated SCP articles from other branches (tagged international), Explained SCPs (tagged explained) and Joke SCPs (tagged joke) should be tagged with at least one Object Class and all applicable SCP Attributes (generally at least two). The scp tag should not be applied until after these other tags are applied. Tales written in the format of an SCP but posted outside any of the previously mentioned SCP series can be tagged foundation-format, but should not be given object classes or SCP attributes, and neither should GoI Formats.

Attribute Tag Categories

To make tagging easier, the SCP Attribute tag list has been divided into 8 categories. Tag names are written in italics, while section names are written in bold. Each tab asks a series of questions, intended to group together similar attribute tags, but if the answer is obviously "no", you should be free to move on to the next question. After reading through an SCP, you should have some idea of which sections will be relevant to the article, but very few anomalies will be fully described by only a single section.

• Entity applies to beings that are alive, including people, animals, plants, and microorganisms, as well as to autonomous entities that are active in some way without technically being alive.
• Animal applies to any animal (including an insect, fish or bird as well as any land animals), to entities or objects that resemble non-human animals, and to effects on animals or on a specific type of animal.
• Biological is for entities and objects that are not alive but are made of biological material or that resemble specific body parts, and to effects that only physically affect alive or biological entities.
• Mental is for effects that act on or are spread through perception, thought, behaviour, or memory.
• Physical is for descriptions of physical form and physical effects, as well as various physics-related properties and effects. While entities may have physical properties and effects, this section is also applicable to inanimate objects and to phenomena affecting them.
• Environment is for descriptions of an entity or object's current location, origin, or natural habitat, as well as describing the kind of environment phenomena may affect or take place in. This category includes both natural and constructed environments, as well as extradimensional and extraterrestrial locations and objects.
• Artificial is for any artifact created by humans, or more rarely by other intelligent beings, as well as specific ways that people can interact with or use anomalous objects, such as using them as part of artistic works. These mostly apply to inanimate objects, but are likely to also apply to autonomous or robotic entities.
• Other is for miscellaneous tags that don't fit neatly into any other section. It's worth reading through at the end to make sure you haven't missed anything, or at the start if none of the preceding sections seem like they'd fit the SCP object you are tagging.

Some of the definitions are rather technical, referencing real science or SCP Wiki pseudoscience, so the aim of this guide is to walk you through SCP tagging one step at a time.

Object Classes and Attribute Tags

Object Classes

• All SCP articles should be tagged with at least one object class tag.
  • The standard object class tags are safe, euclid, keter, thaumiel, apollyon, archon, cernunnos, ticonderoga, neutralized, decommissioned and pending.
  • explained is technically a "Major Page Tag" and not an object class, but may be used as an Object Class on Main Series and joke SCPs as well as Explained SCPs.
  • If an SCP does not have one of these object classes, if its object class cannot be determined from the article's contents, or if it has a non-standard object class, it should be tagged esoteric-class.
  • If an SCP has multiple object classes at the same time, most frequently Safe, Euclid, or Keter and a secondary object class, it should be tagged with all applicable object class tags, which may include esoteric-class.
  • If an article's object class changes over time, either by striking through an outdated object class or by updating the SCP article with a new iteration, only the object class or classes on the final version of the article should be applied as tags.
    • The exception is articles tagged as neutralized, decommissioned or explained, which should be tagged with whatever object class they were before, if that object class is included in the article.

Entity

• Is the entity human or human-like?
  • Any entity that resembles a human or has similar morphology to a human should be tagged as humanoid.
  • If an entity is in fact a human being, then it should have the following tags by default, unless they are overridden by some aspect of its anomalous properties: alive, humanoid, and sapient.
  • If it is a human child, tag it child.
  • Non-human humanoids may or may not also be alive or sapient, but many are both.
  • A cadaver or sculpture can be humanoid without being alive or sapient.
• Is the entity alive, or active in some way without being alive?
  • Unless it is described as dead or its status as a living being is doubtful due to its anomalous properties, any identifiable species of animal, bacteria, fungus or plant should be tagged as alive.
  • For unidentified species or in ambiguous cases, the definition of alive involves an organism responding to external stimuli, consuming energy, and producing waste. Living organisms are also capable of growth and reproduction. While not all of these may be verifiable from the description in an SCP article, if it is a biological entity that requires some form of food to remain active, it is probably alive.
    • While reproduction is an expected property of living beings, creatures that can produce copies of themselves through anomalous means (and not through sexual or asexual reproduction) should be tagged as self-replicating.
  • If an entity is dead but continues to move, it should be tagged as cadaver and reanimation. If it was previously dead but has now been restored to life, tag it alive and reanimation.
  • If the entity doesn't have these traits but is still capable of movement and activity (such as a "living" statue), it should be tagged as autonomous, unless it is robotic. See the Artificial section for additional tags that may apply to non-living entities.
    • If an entity that affects living things is described as a virus, it is biological but not alive, and should get the virus tag. This replaces the contagion tag.
      • A computer virus also get this tag, but is not biological.
• If it is alive or resembles a living thing, what type of organism is it?
  • If the entity is described as a member of a specific species, it should be relatively simple to look up how to categorize it. However, many entities do not belong to any identifiable species.
  • If it is described as a bacterium, or has similar traits to microscopic bacterial life, it is bacteria.
  • If the entity shares traits with plants, particularly if it is capable of photosynthesis, it is a plant.
  • If the entity resembles a tree, it should also be tagged as tree, even if it does not qualify as a plant.
  • Mushrooms, moulds, and yeasts, which do not photosynthesize but feed on decaying matter, should instead be tagged fungus.
  • If the entity shares traits with an organism from the kingdom Animalia (locomotion for at least some of its life cycle, non-photosynthetic metabolism relying on ingesting food, and a fixed bodily structure with restricted growth upon reaching maturity), it should be tagged animal. See the Animal section for tags that apply to entities that are, resemble, or affect specific types of animal.
  • If a group of entities can pass on their anomalous properties to their offspring, they should be tagged species.
• Can the entity alter its own form?
  • If the entity alters its own shape or properties in response to stimuli (voluntarily or otherwise), it is adaptive.
  • If the entity can (voluntarily or otherwise) change its shape or appearance to other fixed forms (including mimicking other entities or objects or an infinite number of variations), it is metamorphic.
  • If the entity can mimic or copy the shape or form of other things, it should be tagged as mimetic.
  • If the entity does not have any shape, or could be described as a "blob", "undifferentiated mass", or "shapeless mass", then it should be tagged as amorphous instead.
• How does the entity interact with other organisms, particularly humans?
  • If the entity hunts other creatures, including humans, for food, it is predatory.
  • If the entity is actively hostile towards humans or the Foundation for reasons other than predation or defence, it is hostile.
• Miscellaneous properties of alive and autonomous entities:
  • If an entity is capable of reasoning and abstract thought (generally conveyed through the ability to communicate) and emotion beyond basic instinctual response (such as affection, hatred, or resentment), it is sapient. Note that while many animals are sentient, in real life the only organism we know of that is sapient are humans. (Hence our name, Homo sapiens.) The sapient tag indicates a roughly human (or greater than human) level of intelligence, and can be applied even if the anomaly doesn't seem particularly clever.
    • If an entity is capable of coherent speech (and isn't just mimicking human voices), it can be considered sapient, although unspeaking entities that display other signs of intelligence can still be considered sapient.
  • If multiple entities share a collective consciousness, they should be tagged hive-mind.
  • If an entity is only active at night, tag it as nocturnal.
  • If an entity is capable of rapid healing whenever it is damaged, it should be tagged as self-repairing.
  • If an entity cannot be destroyed or killed by any means the Foundation has devised so far, it is considered indestructible. This may be because it is impossible to damage, or because it regenerates regardless of how much damage is done.

• There are additional tags that may also apply to different types of anomalous entities, but since these tags are more vague and are also applicable to tales and GoI Formats, they are categorized as Themes - see the Genre Tagging Guide for more information. These tags may be applied to any SCP in which they appear prominently, even if they are not the anomaly the SCP is describing:
  • alien applies to extraterrestrial beings.
  • artificial-intelligence applies to intelligent computer and robotic anomalies.
  • demon applies to entities described as demons or "Tartarean entities".
  • faerie applies to entities inspired by European folklore, described as fairies, fae or the fair folk.
  • ghost applies to the spirits of the dead, described as ghosts or "spectral entities".
  • murder-monster applies to inhuman entities that are hostile or predatory and primarily target humans.
  • superhero applies to both superheroes and supervillains - characters with secret identities, costumes and supernatural powers.

Animal

• These tags apply to any animal of a known species, as well as to objects and to unidentified or hybrid creatures that resemble one or more types of animal.
  • Humans and human-like entities (other than a non-human primate) are covered by the humanoid tag.
• These tags can also apply to phenomena that specifically affect animal life, or a particular type of animal.
• Is it an invertebrate? These organisms lack a backbone, and may possess a shell or exoskeleton instead of an internal skeleton.
  • Multiple types of invertebrate have their own tag:
    • arachid applies to eight-legged arthropods (spiders, scorpions, mites, ticks).
    • insect applies to six-legged, three-segment arthropods such as ants, beetles, and flies.
      • Bees should also be tagged bee.
      • Butterflies, moths, and skippers should also be tagged butterfly.
    • crustacean applies to another group of arthropods (crabs, lobsters, shrimp, isopods, barnacles).
    • arthropod applies to all other animals with exoskeletons, segmented bodies, and jointed appendages, including centipedes and millipedes.
    • cephalopod applies to marine mollusks with tentacles (cuttlefish, octopus, and squid).
    • worm applies to limbless invertebrates with long, flexible bodies. This is a loose grouping rather than a taxonomic category, but conveniently most things that are categorised as worms have it in their name (earthworms, flatworms, roundworms).
    • invertebrate applies to all other invertebrates, including slugs, snails, starfish, jellyfish, coral, and sea urchins.
    • Keep in mind that both the invertebrate and arthropod tags are superseded by the other more specific tags most of the time.
• Is it a vertebrate? These organisms have a backbone and an internal skeleton.
  • amphibian applies to cold-blooded semi-aquatic unscaled animals, including frogs, toads, and salamanders.
  • bird applies to warm-blooded animals with feathered wings, including both flying and flightless birds.
  • fish applies to cold-blooded aquatic animals with gills and fins.
    • Sharks, defined by their cartilaginous skeleton, streamlined body, and tough skin with tooth-like scales, should also be tagged shark, as should rays and skates.
  • reptile applies to cold-blooded, scaled animals with lungs, such as lizards, crocodiles, and turtles.
    • Snakes can also be tagged snake.
    • Extinct prehistoric reptiles can also be tagged dinosaur. This includes all non-avian dinosaurs but not modern birds, as well as pterosaurs and extinct marine reptiles from the same era (plesiosaurs, ichthyosaurs, mosasaurs).
    • Draconic creatures inspired by various traditions can be tagged dragon, and will usually also count as a type of reptile and animal.
  • Is it a mammal? Types of mammal with their own tags, and example species:
    • bear - brown, black, polar, panda.
    • bovine - cattle, buffalo, bison.
    • canine - dogs, wolves, coyotes, jackals.
    • cetacean - whales, dolphins, porpoises.
    • deer - deer, elk, moose.
    • equine - horses, zebra, donkeys.
    • feline - cats, including big cats like lions and tigers.
    • non-human primate - apes, monkeys, lemurs.
    • rabbit - rabbits, hares.
    • rodent - mice, rats, squirrels, beavers.

Biological

• Is it made of biological material?
  • If the entity isn't technically alive but consists of organs or biological tissue, or is otherwise composed of organic compounds such as protein, fat, or carbohydrate, it is biological instead.
  • If it used to be alive but is now dead, tag the corpse as a cadaver.
• Does it affect or consist of specific parts of the body?
  • If it is or affects blood, tag it blood.
  • If it is or affects teeth, tag it dental.
  • If it is, resembles, or affects eyes, tag it ocular.
  • If it is a severed limb or affects limbs in a particular way, tag it extremity.
  • If it affects the reproductive system or sexual organs, it may be tagged reproductive if it primarily affects conception or pregnancy, or sexual if it primarily affects sexual intercourse.
  • If it consists of bones or cartilage, or affects skeletal tissue, tag it skeletal. An entire skeleton should also be tagged cadaver.
• How does the entity affect other organisms?
  • If it affects dead bodies, tag it cadaver. If it restores them to life, tag it reanimation.
  • If the entity infects other entities (such as animals or humans) and spreads among them, it is probably a contagion. A contagion is not necessarily a biological process caused by an identifiable organism, but it may be one.
    • contagion may be used together with bacteria, but should be replaced by virus.
    • microscopic fungi, protists and biological prions may also cause a contagion.
    • If a multicellular entity (usually not microscopic) subsists by infesting a host organism and feeding off its host, it is a parasite, and should not also be tagged as a contagion. Parasitoids, which kill their host rather than just feeding off it, are included in this definition. A parasite may also be a specific type of animal.
  • If the entity hijacks the reproductive system of another entity, such as a creature that grows and matures in the womb of another type of creature, then it should be tagged as reproductive (and probably also as a parasite).
  • If an entity produces a biological molecule that is hazardous to humans, it should be tagged as a biohazard.
  • If a non-biological chemical is hazardous to health, it should be tagged toxic.
  • If it is specifically causing drunkenness through ethanol intoxication, or if being drunk affects an entity's anomalous properties, tag it alcohol.
• Miscellaneous biological properties:
  • If an anomaly can affect the genome or is encoded by a specific gene or set of genes, tag it genetic.
  • If an anomaly is used or is intended for use as a medical device, or has any medical significance other than simply causing disease, tag it medical.
  • If an anomaly affects sexual organs, sexual activities, or concepts related to sex, in a way that is distinct from simply having anomalous reproductive methods, tag it as sexual. While this is distinct from the _adult content marker, sexual articles do often warrant an Adult Content Warning due to the subject matter.

Mental

• Does perceiving it have an effect on the mind? Does it alter the senses?
  • If observing an object, entity, or effect triggers an anomalous response or another effect, it is a cognitohazard.
  • If the perceived effect cannot be detected by other individuals or by recording devices, it is causing a hallucination.
  • If the effect causes objects or entities to be perceived differently from other people (such as being able to sense things normally too faint or indistinct to be sensed, having a disconnect in our sensory perception, or even losing the ability to use a sense entirely), it should be tagged as sensory sensory
  • The cognitohazard, hallucination and sensory tags should be used in conjunction with one or more of the five sensory tags:
    • If it affects sight or an effect is triggered by seeing it, other than by being exposed to bright light or harmful radioactive activity, it is a visual effect.
    • If it affects hearing or an effect is triggered by hearing it, other than by being too loud or through harmonic disruption (which would be acoustic), it is an auditory effect.
    • If it affects the sense of smell or an effect is triggered by smelling it, other than through the ingestion of toxic or otherwise harmful chemicals, it is an olfactory effect.
    • If it affects the sense of taste or an effect is triggered by tasting it, other than through exposure to a harmful substance, it is a gustatory effect.
    • If it affects the feeling of touch or an effect is triggered by experiencing the texture or consistency of a substance, rather than merely through contact with it, it is a tactile effect.
• Is the effect related to information or knowledge about it?
  • If directly or indirectly observing an entity or object alters its properties, it is observational.
  • If merely knowing of the existence of the object, entity, or location can trigger an anomalous effect, even without directly perceiving it, it is an infohazard.
  • If the anomaly or information related to it is capable of memetic propagation; that is, individuals exposed to it can reproduce and spread the effect to others, it is a memetic effect. This replaces the contagion tag.
    • A memetic effect can be distinguished from a cognitohazard or infohazard (although it may still be applied in conjunction with either tag) because the information itself is anomalous and infectious, and does not require any exposure to the original object or entity to spread.
  • Conversely, if the effect suppresses knowledge and understanding of itself or of another idea or concept, it is antimemetic.
  • If the object, entity, or location affects documentation or descriptions of itself (often through a Mental effect on the people compiling the documentation), it has a meta effect.
• Does it affect the thoughts and behavior of individuals exposed to it?
  • A compulsion refers to a temporary urge compelling people to do something they would not normally do following exposure to an anomaly.
  • A mind-affecting anomaly can permanently alter thinking, including behaviour and overall intelligence, and so is also capable of making people do things they would otherwise never do.
    • A compulsion is usually a mild and temporary urge, while a mind-affecting effect can cause an intense and lasting obsession.
  • A memory-affecting anomaly can remove, alter, or impart memories into people that interact with it, which may or may not be permanent.
  • If exposure to a substance or effect results in a desire to experience it again, in a manner similar to chemical addiction, it is addictive.
  • Any of these effects may be caused by a cognitohazard, infohazard, or memetic effect, but they could instead be propagated by mere proximity to an entity or object, without any awareness of it.
• Can it be used to convey information?
  • If an entity can convey or read emotion, feelings, or sensations through anomalous means, it is empathic.
  • If an entity can convey information through anomalous means rather than through conventional forms of communication like speech and writing, it is telepathic.
  • If the information itself is anomalous, or if the knowledge is absorbed, generated, stored, or granted through an anomalous process, tag it knowledge.
    • If this knowledge relates to future events, tag it predictive instead.
  • If the anomaly is an anomalous language, or if it imparts understanding of or communicates through an anomalous language, give it the language tag.
• Miscellaneous mental effects:
  • If the article explicitly confirms that an anomaly has detectable effects on the brain, tag it neurological.
  • If an anomaly is related to sleep, such as inducing unconsciousness or only affecting people who are dreaming, tag it sleep.

Physical

• Does it take the form of a three-dimensional geometric shape?
  • If it is spherical, tag it sphere.
  • If it has any number of flat faces and straight edges, it is polyhedral. Cubes are the most commonly seen polyhedron, but there are many other polyhedra with different numbers of faces.
• What is its physical composition and properties?
  • If it is specifically described as an anomalous chemical, or as producing chemical compounds in an anomalous way, it is chemical, unless those compounds would be categorised as a biological molecule (polypeptides, lipids, carbohydrates).
    • If it degrades other materials through a chemical process, it is corrosive.
    • If it harms living beings that are exposed to it, it is toxic.
    • If it is a drug, it may have Biological or Mental effects. If it specifically compels people to take more of it, it is addictive.
  • If it is or generates a gas, a substance that will freely disperse to fill any container it is placed in, tag it gas.
  • If it is or generates a liquid, a substance that flows but maintains a fixed volume, tag it liquid.
  • If it does not have physical mass or otherwise cannot be touched but is not a gas or liquid, it is intangible.
  • If it produces copies of itself through anomalous means, it should be tagged as self-replicating.
  • If it produces matter from nothing (including copies of itself), without any evidence of transporting it from somewhere else (including extradimensional, extraterrestrial, or temporal locations), then it should be tagged ectoentropic, as the generation of mass or energy is a reversal of entropy.
  • Conversely, if it has anomalous properties that affect or are affected by entropy, particularly accelerating the decay of other objects, it is entropic.
  • If it is otherwise described as anomalously interacting with the laws of thermodynamics, tag it thermodynamic.
• Has the Foundation attempted to move or destroy it?
  • An object that cannot be moved by any means known to the Foundation is considered immobile.
    • This excludes objects that are so large that they are not expected to be portable, unless the Foundation specifically tries and fails due to an anomalous effect.
  • If it is capable of being damaged or harmed but can quickly restore itself to its normal condition through anomalous means, it should be tagged as self-repairing.
  • If it cannot be destroyed by any means the Foundation has devised so far, it is considered indestructible.
• Does it physically affect itself or other objects through anomalous means?
  • If it would not normally be capable of movement but moves through anomalous means, it is tagged as mobile.
  • If it moves between locations without occupying the space in between, it is instead tagged teleportation.
  • If it manipulates other objects through anomalous means, it is telekinetic.
  • If it alters the shape or substance of other entities or objects, tag it transfiguration.
• Does it produce or respond to a particular kind of energy? Does it react to a lack of energy?
  • If energy is generated without any apparent source, it should be tagged ectoentropic.
    • The creation of energy violates the First Law of Thermodynamics and reduces the entropy of the universe, hence the name.
  • If it produces or is spread through sound waves passing through air or liquid, it is acoustic.
    • This is distinguished from an audible effect by having effects that are not Mental, and rely on the physical generation and propagation of sound.
  • If the effects are caused or spread by vibrations passing through solid objects, tag it vibration.
  • If it generates, stores, or uses electricity, it is electrical.
    • If it is an electrical appliance or other device, see the Artificial section for other tags that may apply.
  • If it is magnetic or exhibits traits of magnetic charge or attraction, it is magnetic.
  • If it generates, stores, or uses electromagnetic fields, tag it electromagnetic.
  • If it transmits information through radio waves or other electromagnetic means, tag it transmission.
  • If it is composed of fire, affects fires, or enables combustion to occur, tag it fire.
  • If it is activated by, triggered by, or spreads through changes in temperature (increases or decreases), it is thermal.
  • If it has anomalous properties that affect or are significantly affected by gravitational force, tag it gravity.
  • If it is triggered, activated, or propagated by the presence or absence of visible light, or if it produces visible light, tag it light.
  • Conversely, if it is triggered, activated, or significantly affected by the shadows cast by objects, tag it shadow.
  • If it emits harmful radiation or affects radioactivity, tag it radioactive.
• Is it described using terms like ontokinesis, reality-bending, or thaumaturgy/thaumatology?
  • If it has effects described as ontokinetic, reality-bending, or reality-warping, tag it reality-bending. This replaces the ectoentropic tag, and identifies an object or entity as being able to directly alter reality through anomalous means.
  • If it has effects described as "thaumaturgic" or as (applied) "thaumatology", which are pseudo-scientific terms for magic and the study of it, tag it thaumaturgy.
  • Avoid using these two tags together, unless they are two distinct classes of phenomena involved in the same anomaly.
• Does it have effects on space and time?
  • If it warps space, it should be tagged as spatial.
    • Common examples include containers being bigger on the inside than on the outside, paths connecting two locations being shorter than they should be, and areas with "non-Euclidean" geometries that should be impossible in 3-dimensional space.
  • If it displaces energy or matter into the past or the future, enables itself or others to travel to another time period, or affects the passage of time experienced by an object or entity, it is temporal.
  • If it was specifically sent back from a later period of time to an earlier one (even if the origin and destination time frame are both in the past), it should be tagged future.
  • If a temporal effect results in a time loop, it should also be tagged loop.
  • If time travel results in a time paradox, it should also be tagged paradox.
  • If the object or entity allows is some sort of gateway or aperture leading to another place, another time period, or an extradimensional or extraterrestrial location, it should be tagged as a portal.
    • See the Location section for more information about the use of these terms.
• Is it notably small?
  • If it is a miniature version of an object it resembles, tag it miniature.
  • If it is too small to be seen or to meaningfully observe details with the naked eye, tag it microscopic.
• Miscellaneous physical descriptors:
  • The loop tag can refer to anything engaged in a repeating loop of activity, even if no temporal effect is responsible.
  • The paradox tag can refer to anything involved in a paradoxical situation, even if no temporal effect is responsible.
  • The transmission tag can apply to any transmission of information, even if no electromagnetic radiation is detectable.

Environment

• Where is it located? Where was it found? What is its natural environment?
  • If it floats or is capable of flight, it is airborne.
  • If it is located underwater or is adapted for swimming, it is aquatic.
  • If it is located underground or is adapted for burrowing, it is subterranean.
  • If it is from, located in, or provides access to an alternate timeline, an alternate reality, or a plane of existence separate from our own, it should be tagged as extradimensional.
    • If the anomalous effect manifests as an opening into said timeline, reality, or plane (no matter how small or temporary) through which objects or entities can be moved, it is also a portal.
  • If it is confirmed that it is from outer space or enables travel through outer space, it should be tagged as extraterrestrial.
• Is it a specific geographic location? Does it affect the natural world?
  • An anomalous location that is not a town or city should be tagged location.
  • An anomalous location that is an island in a body of water, or any anomaly that affects islands or archipelagos, should be tagged island.
  • An anomalous location with a large number of trees (forest, woodland, grove, orchard), or any anomaly that affects this kind of area, should be tagged forest.
  • An anomalous weather event, or an anomaly that affects or is affected by significant weather events, should be tagged meteorological.
  • An anomalous geological formation (cave, cliff, mountain, valley, volcano) should be tagged geological, as should any anomaly that affects this kind of formation, or that causes significant geological events (earthquakes, landslides, sinkholes).
  • An anomaly that affects the entire planet should be tagged planet instead of geological.
    • This tag can apply to both planet Earth and to other planets.
• Was it built by humans? Does it affect human structures?
  • If an anomalous location encompasses an entire artificial structure or a specific portion of it, it should be tagged as structure.
    • If that structure was intended for human occupation (such as a home, office, or factory), then it should be tagged as a building instead.
  • If an anomalous location encompasses an entire settlement (such as a town or city) or a significant portion of a settlement, then it should be tagged city instead of location or building.
  • If it affects one or more libraries (buildings containing books for people to read or borrow), tag it library.
• Is it located outside of Earth's atmosphere?
  • If it is located in outer space, tag it extraterrestrial.
  • If it is a small natural or artificial satellite in orbit around Earth or another celestial body, tag it satellite.
    • Artificial satellites may need additional Artificial tags.
  • If it is, affects, or is related to a large natural satellite or moon in orbit around a planet, including Earth's moon, tag it moon instead of satellite.
  • If it is or if it affects a planet other than Earth, tag it with both planet and extraterrestrial.
  • If it is, affects, or is related to a sun, including Earth's sun but also the stars of other planets, tag it sun.

Artificial

• Was it made by an intelligent creator?
  • If it was created, intentionally or otherwise, by the SCP Foundation itself, it is foundation-made.
    • This only includes objects whose creation was a direct result of specific actions by the Foundation and its employees, and excludes the spontaneous occurrence of anomalous phenomena at Foundation sites containing a large number of anomalies.
  • If it was made by an ancient civilization and then discovered by archaeologists, it is archaeological.
  • Was it created for artistic expression?
    • If the object is a three-dimensional representation, it is a sculpture. If it is a full-body representation of a person, apply the humanoid tag. If it is a representation of an animal, apply the appropriate Animal tags, if any are applicable.
    • If the object is a film or movie, or is otherwise related to filmmaking, it is cinema.
    • If the object is musical in nature, whether it is a musical composition or an instrument that enables the creation, composition, or performance of music, it is musical.
    • If it is used in an artistic performance, such as a dance or play, it should be tagged performance.
    • If it is a photograph, a collection of photographs, or a camera for taking still images, tag it photographic.
    • If the object has artistic significance but doesn't fall into any of the aforementioned categories, it should be tagged as artistic.
    • Anomalies that can create or affect art may also be tagged artistic, or with a more appropriate subtag such as cinema, musical, performance, photographic or sculpture.
  • Was it created to manipulate other things?
    • If the object was primarily intended to be used to kill, harm, or otherwise disable or impair another living thing (such as a gun or combat knife, but not a wood axe or swiss army knife), it is probably a weapon.
    • If the object is hand-held and used for a specific purpose, and doesn't fall under weapon, it is a tool.
  • Was it created to perform some kind of household, commercial, or industrial function?
    • If the object is used to perform calculation or data manipulation, it is a computer.
      • A computer should be further tagged as mechanical or electronic, as appropriate (see below).
      • Computers and robotic entities may be affected by a contagion. If it is specifically described as a computer virus, tag it virus instead of contagion.
      • If it makes use of a connection to the internet, it is online
    • If the object is a household appliance (defined as something that performs work that enables or improves quality of life in a home, such as a television, microwave, or lamp), it is an appliance.
    • If the object was intended to be played with, it is a toy.
    • If the object is primarily intended to transport passengers or cargo, it is a vehicle.
      • If the vehicle primarily flies or moves through water, then it should also be tagged as airborne or aquatic, as appropriate.
    • If the object is primarily intended to be worn:
      • If its purpose is primarily for comfort or protection (such as in the case of body armor, a coat, or a hat), it is clothing.
      • If its purpose is primarily decorative or for purposes other than survival (such as a wristwatch or a necklace), it is jewelry.
  • If the object is primarily intended to hold or carry information:
    • If the object has decorative or functional designs written on, carved or cut into its surface, it is inscribed.
      • If it primarily holds textual information in a human-readable format (such as a book or written contract), it is a document.
      • If it holds information using a method other than text (such as a video clip or audio recording), it is media. Electronic media also falls into this category, as any data on a computer storage device is not directly human-readable.
        • If the contained data is also primarily textual, it may be both document and media.
        • If it is a collection of digital images, it may be both media and photographic.
        • Media distributed through the Internet should be tagged as online
    • If it consists of food or drink, it should be tagged food.
  • If an artificial object does not fall into any of the categories above, then it should be tagged as an artifact.
  • Does the object use power?
    • If the object is powered by electricity, then it should be tagged as electrical.
    • If the object operates using semiconductors (such as those in computer chips) to control the flow of electricity within it, it is electronic.
    • If the object has moving parts, it is probably mechanical.
      • If those moving parts are mostly gears and springs, it should instead be tagged as clockwork.
      • If those moving parts are electronic, it should instead be tagged as robotic.
• How do people make use of the object?
  • If the object contains alcohol (ethanol) or is used in the preparation or distribution of alcoholic drinks, tag it alcohol.
  • If the object is intended to be used as a medium of exchange, or if it affects or is activated by money, tag it currency.
    • If the act of trading triggers anomalous effects, it should also be tagged exchange.
  • If it is used as part of a game, or activated by one, tag it as game. Games are defined as methods of play, especially competitive ones, that can be won or lost by skill, strength, or luck.
    • A video game would also be tagged as media, while most other types of game would either be tagged sport or toy.
    • Sport is defined as a game involving physical exertion and skill, in which one or more individuals compete against other individuals or teams. Sports equipment should be tagged as clothing or tool as appropriate.
  • If it is a medical device, tag it medical.
  • If it is military equipment, tag it military.
  • If it has religious significance, tag it religious.

Other

• Is it an event?
  • A singular event that significantly changed reality in some way is an anomalous-event.
  • Recurring and widespread anomalous activity that cannot be directly linked to a physical source should instead be tagged as a phenomenon.
  • If an anomaly is causing the end of the world as we know it, and a specific type of K-Class scenario is named, it should be tagged k-class-scenario.
• Are humans interacting with the anomaly in a specific way?
  • If it affects the preparation or distribution of alcoholic drinks, tag it alcohol.
  • If it specifically affects children, tag it child.
  • If it resembles, affects, or involves one or more clowns, which may either be human or a type of anomalous entity, tag it clown.
  • If an anomaly involves or is triggered by some form of exchange, including use of both barter and currency and the trade of both physical and intangible goods, tag it as exchange.
    • If it specifically affects or is activated by money, tag it currency.
  • If the anomaly is part of a military unit or has other military significance, tag it as military.
  • If the anomaly is worshipped by a religious group or has other religious significance, tag it as religious.
  • If it is triggered by or activated through ritualistic behaviour, tag it as a ritual.
  • If the anomaly is identified as a fictional narrative, or if it is related to or propagates through narrative information or documents, tag it as narrative.
  • If the anomaly affects or is affected by its documentation, or if its containment procedures require it to be documented in a specific way, it is meta.
    • Meta anomalies are often either infohazards or narrative anomalies, but do not have to be, as long as they interact with their own documentation in some way. Non-standard SCP documentation due to descriptions of meta effects is often referred to as a format screw.
• Miscellaneous attributes:
• If it is or affects a purely non-physical concept, tag it concept.
  • While this should not be used in conjunction with tags describing any Physical properties, alterations to some concepts might have physical effects.
• If it affects a number, number system, or mathematical equation, or otherwise has mathematical significance, tag it mathematical.
• If it alters the probability of certain events or outcomes occurring, tag it probability.
• If no instances of an SCP object are contained, or if a singular SCP entity is only partially contained, it should be tagged uncontained. Uncontained SCPs may have never been contained, or may have previously been contained before breaching containment. When used as an object class, this is an esoteric-class.

If you've applied an object class and are confident you've added all applicable SCP attributes, you may also apply the scp tag to the SCP article.