APIs in the Metaverse—A Systematic Evaluation
Abstract
:1. Introduction
- R1.
- What APIs are currently available in the Metaverse?
- R2.
- What information can be retrieved through the available APIs?
- The study gives an overview of which virtual worlds from a sample offer APIs.
- The paper provides a guide to information accessible through APIs provided by virtual worlds.
- The study compares APIs regarding the available information and identifies generic weaknesses and future research directions.
1.1. Related Work
1.2. API Technology
- SOAP APIs: Simple Object Access Protocol (SOAP) APIs are protocol-based and known for their standardized format and extensive feature set, including built-in error handling and security [17].
- Communication Patterns: RESTful APIs operate on a request-response model, SOAP APIs use a service-oriented approach, and GraphQL allows for dynamic queries and mutations [18].
2. Methodology
2.1. Sample Selection
- Persistence: The platform’s ability to offer continuous, uninterrupted virtual experiences is essential. Persistence ensures that the digital environment and user-generated content remain accessible over time.
- Immersiveness: An essential attribute of the Metaverse, immersiveness refers to how convincingly the platform can engage users in a virtual environment. It includes sensory engagement and the depth of interaction within the virtual world.
- Social Interaction: The extent to which the platform supports and facilitates user interaction and social connectivity. This criterion evaluates how the platforms enable community building, collaboration, and social experiences.
- Accessibility: Accessibility is critical for broad adoption and usability. It encompasses the ease of access to the platform, user-friendliness, and the inclusivity of different user groups.
- Decentralization: Given the evolving nature of the Metaverse, decentralization is a forward-looking criterion. It reflects the platform’s approach to governance, data control, and power distribution among users and developers.
2.2. API Research Methodology
- Website Analysis: The official websites and developer documentation of the Metaverse platforms were examined. This analysis focused on identifying publicly available APIs, their features, and the scope of access they provided.
- Community Engagement: Active engagement with the developer community was conducted mainly through Discord channels. These discussions offered insights into the practical uses of the APIs and additional information not available in official documentation.
- Direct Correspondence: Where necessary, direct communication with the development teams of the Metaverse platforms was established via email. This method was employed to clarify details, gain further information, and request access to APIs where public information was insufficient.
3. Results
3.1. Identification and Evaluation Process
- API Existence Check: Determining if the Metaverse platform offers any API.
- Public API Assessment: Identifying whether the APIs are public, ensuring external users and developers can access them.
- Accessibility Verification: Confirm these APIs’ ease of access and usage, including the availability of documentation and developer support.
- Axie Infinity: A digital pet universe where players breed, raise, battle, and trade fantasy creatures called Axies [26].
- Decentraland: An open-world virtual reality platform that leverages the Ethereum blockchain to provide a decentralized user-owned environment [27].
- Roblox: A platform that revolutionized user-generated content, providing a suite of tools for users to create their own experiences [28].
- Second Life: One of the earliest and most mature virtual worlds, offering rich user interactions and a complex economy [29].
- Upland: A virtual property trading platform mapped to the real world, allowing users to buy, sell, and trade virtual properties [30].
- Voxels: Focused on simplicity and ease of use. This platform allows users to create and trade virtual assets on the blockchain [31].
- VRChat: A social virtual reality platform that enables users to interact with others in various immersive, user-created worlds [32].
3.2. Available APIs
3.2.1. Comprehensive Overview of Available APIs
3.2.2. Details on Selected API Endpoints
- Decentraland’s Tiles API: The Tiles API in Decentraland has been updated to a more efficient v2 endpoint. It returns detailed information about all tiles in the map in a new, more readable format. This API is crucial for accessing comprehensive data about virtual land parcels in Decentraland, offering insights into the layout and distribution of land.
- Decentraland’s Estates API: The Estates API in Decentraland allows users to retrieve metadata about an estate based on its ID. An estate represents a building or facility often stretching across multiple tiles. This functionality is essential for accessing detailed information about estate properties, including their ownership and characteristics.
- Voxels Parcel API: The response provides detailed information about a parcel in the virtual world. An example response includes data such as the parcel’s ID, dimensions, location coordinates, contributors, and ownership details. However, a blockchain explorer like Etherscan [30] is essential for comprehensive insights, especially on transaction history and ownership changes. It complements the API by providing deeper transactional data, which is crucial for understanding the full economic context of each parcel.
- Roblox’s Avatar API: In Roblox, each user is represented by a customizable avatar. The Avatar API provides functionalities for character model customization, allowing users to interact with experiences and personalize their avatars with a wide range of clothing and accessories available in the Roblox Marketplace. This API is a cornerstone for user identity and personalization within the Roblox platform.
- Second Life’s Map API: The Map API of Second Life enables the integration of dynamic Second Life maps into websites or applications. It provides a way to embed real-time maps showing the virtual world’s layout, including regions and significant landmarks. Developers can use this API to create interactive map features for users, enhancing navigation and spatial awareness in the Second Life Metaverse.
3.2.3. Comparison of Available APIs
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Metaverse Platform | Accessible Public API Available |
---|---|
Axie Infinity | Yes |
Captic | No |
Decentraland | Yes |
EngageVR | No |
Horizon Worlds | No |
MONA | No |
Roblox | Yes |
Sansar | No |
Second Life | Yes |
Somnium Space | No |
Spatial | No |
The Sandbox | No |
Upland | Yes |
Voxels | Yes |
VRChat | Yes |
APIs Identified | Description and Key Features |
---|---|
Tiles API [33] | The endpoint returns all tiles in the Decentraland map. This API is key for accessing detailed data about the virtual land parcels in Decentraland. In Decentraland, a tile represents the smallest unit of land, similar to a single square on a chessboard. These tiles are collectively known as parcels, the basic building blocks of the Decentraland world. |
Parcel API [33] | The endpoint returns metadata about a specific parcel by its coordinates using the OpenSea Metadata Standard [34]. A parcel in Decentraland is a single tile or a unit of land that players can own and develop. Parcels are 3D spaces where users can create experiences, games, or other interactive content. |
Estates API [33] | The endpoint provides metadata about an estate that comprises several contiguous parcels (or tiles) by its ID. An estate is a larger piece of land made by grouping adjacent parcels. Estates allow for the creation of more extensive developments. |
Districts API [33] | The endpoints return information about all districts or specified districts in Genesis City. Districts in Decentraland are large areas comprising multiple parcels, usually centered around a specific theme or community. They are akin to neighborhoods or sectors within a city, providing a communal space for users with similar interests. |
Map API [33] | The endpoint returns a PNG of the genesis map, customizable via various query parameters such as width, height, and center coordinates. It provides a bird’s-eye view of Decentraland, showcasing the layout of parcels, estates, and districts. |
Event API [35] | The endpoint provides information about upcoming events. It includes details like event names, descriptions, dates, and coordinates, facilitating the discovery and participation in various virtual events. |
APIs Identified | Description and Key Features |
---|---|
Registration API [36] | This API allows for registering Second Life residents directly from a web page. It streamlines adding new users to the Second Life community by integrating the registration process into external websites. |
Map API [36] | This API allows for embedding Second Life maps onto web pages. This is particularly useful for integrating Second Life features into external platforms or creating custom user interfaces. |
Live Data API [36] | Linden Lab provides live data feeds that offer real-time information relevant to the Second Life environment, such as current events or user activities. |
Inventory API [36] | This API provides information on agent inventory within Second Life. It is crucial for managing and accessing the inventory data of users. |
Search API (unofficial) [37] | This API enables searching within Second Life for events, groups, people, and places and also facilitates searching the Second Life Wiki. |
APIs Identified | Description and Key Features |
---|---|
Parcels API [38] | Returns details about every parcel in Voxels, including the owner, collaborators, description, and geometry. |
Single Parcel API [38] | Provides basic information for a specific parcel in Voxels when given the parcel’s ID as a parameter. This API focuses on individual parcel data. |
AllFeaturesParcel API [38] | Returns all features inside a specific parcel based on the provided parcel ID and goes deeper into the details of a specific parcel, revealing all its features (e.g., items or structures) when provided with the parcel’s ID. |
Suburbs API [38] | The endpoint offers information about all suburbs in Voxels, including their characteristics and locations. |
Islands API [38] | Provides a list of all islands in Voxels and their geometric data, giving a comprehensive overview of these distinct areas within the virtual environment. |
Womps API [38] | Returns the last 100 womps (user-generated messages or actions) and their associated information in Voxels. |
Avatars API [38] | The endpoint gives information about avatars, including details of their corresponding parcels. This API links virtual characters to specific locations in Voxels. |
Collectibles API [38] | The endpoint provides information on all collectibles within Voxels, including details about each collectible item. |
APIs Identified | Description and Key Features |
---|---|
Users API [39] | This API handles direct Roblox user information. It provides access to user-related data, such as profiles, statistics, and other critical user-specific details. |
Avatar API [39] | This API focuses on the customization of player avatars. It includes endpoints for modifying and retrieving information about player avatars. |
Catalog API [39] | Enables browsing and searching for catalog items. It also recommends content and user-based catalog items. |
Games API [39] | This API provides valuable data for game discovery. It includes endpoints for retrieving detailed information about games available on Roblox. |
Groups API [39] | Manages groups within Roblox, including creating, managing, and moderating user groups. This API is essential for community building and management on the platform. |
Presence API [39] | It contains all endpoints for managing user presence. It helps track and display the online status and activity of users. |
Inventory API [39] | It focuses on viewing (but not granting) ownership of items. Users must manage and view their in-game inventory, including items owned, collected, or earned through gameplay. |
Premium Features API [39] | This API plays a crucial role in managing premium subscriptions and features available to users who opt for the premium service on Roblox. |
APIs Identified | Description and Key Features |
---|---|
Item API [40] | This API includes endpoints for listing all runes, charms, and other items and retrieving specific items by ID. It is used for managing the different items available in the game. |
User Item API [40] | With the query parameter of the UserID, all Items of the given user are displayed in the format of the Item API. |
User Map API [40] | With the query parameter of the UserID, all the cleared Chapters of the given user are displayed. |
User Fighter API [40] | With the query parameter of the UserID, all the fighters of the given user are displayed. |
Leaderboard API [40] | This API Lists the current leaderboard of players and the current season leaderboard. The maximum number of players in the response object can be limited with query parameters. |
Season API [40] | This API shows basic information about the current Season. |
APIs Identified | Description and Key Features |
---|---|
Tracks API [41] | This API response provides an overview of a track in Upland, offering details like location, physical attributes, and conditions that can be used for game mechanics or player decision-making. |
Tracks Buildings API [41] | This API response describes a building in Upland, including its physical characteristics and location. |
Cities API [41] | This API response provides information about cities in Upland, listing each city with a unique identifier and its name. |
Properties API [41] | This API lists information about properties in Upland, detailing their location, status, and related financial information. |
APIs Identified | Description and Key Features |
---|---|
Avatars API [42] | This endpoint manages avatar data within VRChat. It provides details such as the avatar’s unique ID, author information, creation and update timestamps, and description. The API also includes the avatar’s image URLs, release status, tags, and unity package details, which are crucial for avatar customization and management. |
Groups API [42] | This endpoint handles group-related data in VRChat. It includes the group’s ID, name, short code, and other descriptive information. The API also manages group icons, banners, owner details, member count, and tags, offering insights into group characteristics and dynamics. Additionally, it covers galleries within groups, encompassing details like ID, name, description, and roles for viewing and submitting content. |
Users API [42] | This endpoint provides comprehensive user profile information in VRChat. It includes bio, current avatar images, display name, user ID, friendship status, and platform information. The API also covers status descriptions, tags, user icons, and location, which are essential for user profile management and social interaction within VRChat. |
Worlds API [42] | Provides detailed information about the virtual worlds or experiences within VRChat. Key data includes the world’s unique identifier, author information, capacity, recommended capacity, creation and update timestamps, and encompasses retrieving world metadata and exploring world categories. |
Economy API [42] | This Endpoint is essential for managing VRChat’s virtual economy and user subscriptions and manages transactions and subscriptions within VRChat. It details transaction ID, status, subscription information (including ID, steam item ID, amount, description, period, and tier), sandbox status, creation/update timestamps, and steam-related information. |
Available Information | Decentraland | Second Life | Voxels | Roblox | Axie Infinity | Upland | VRChat |
---|---|---|---|---|---|---|---|
Virtual Property Information (e.g., ownership or characteristics of land, parcels, estates) | X | X | X | ||||
District, Island, or Neighborhood Information (e.g., community topics) | X | X | X | ||||
Map | X | X | X | ||||
Event and Experience Information (e.g., topics, types, dates, location) | X | X | X | ||||
Admin Functions (e.g., register users, user groups, season data) | X | X | X | X | |||
Live Data (e.g., user activity, leader board, presence, messaging, economy) | X | X | X | X | X | ||
User and Avatar Data (e.g., public account data, inventory) | X | X | X | X | X | ||
Asset and Collectible Information (e.g., properties, IDs) | X | X | X |
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Traub, M.; Weinberger, M. APIs in the Metaverse—A Systematic Evaluation. Virtual Worlds 2024, 3, 157-170. https://doi.org/10.3390/virtualworlds3020008
Traub M, Weinberger M. APIs in the Metaverse—A Systematic Evaluation. Virtual Worlds. 2024; 3(2):157-170. https://doi.org/10.3390/virtualworlds3020008
Chicago/Turabian StyleTraub, Marius, and Markus Weinberger. 2024. "APIs in the Metaverse—A Systematic Evaluation" Virtual Worlds 3, no. 2: 157-170. https://doi.org/10.3390/virtualworlds3020008
APA StyleTraub, M., & Weinberger, M. (2024). APIs in the Metaverse—A Systematic Evaluation. Virtual Worlds, 3(2), 157-170. https://doi.org/10.3390/virtualworlds3020008