Screeps Arena spawnCreep(): Find Your Spawn
Find your Screeps Arena Spawn with getObjectsByPrototype(), call spawnCreep(body), read object or error results, and avoid mixing Arena with MMO syntax.
ARTICLE LIBRARY
Practical Screeps articles for the problem you need to solve
Browse 81 published guides by system, difficulty, content type, or topic. Start with What Is Screeps? A Programming Strategy Game or follow the beginner sequence through How to Combine Your First Screeps Room Loop.
Screeps: Clean Dead Creep Memory Safely
Clean stale Memory.creeps entries by comparing them with Game.creeps. Delete only confirmed dead names and keep custom task indexes in sync.
Screeps: Why Game.rooms[roomName] Is Undefined
Learn why Game.rooms[roomName] is undefined without current room vision, how to guard live Room reads, and why Memory.rooms does not prove visibility.
Screeps renewCreep(): Requirements, Cost, and Return Codes
Learn StructureSpawn.renewCreep() requirements, TTL and Energy formulas, Boost and CLAIM limits, return codes, and how to verify renewal on the next tick.
Screeps Lab boostCreep(): Requirements, Usage, and Return Codes
Learn StructureLab.boostCreep() requirements, bodyPartsCount usage, return codes, current-tick scheduling, and how to verify exact boosted body parts afterward.
Screeps RoomVisual: Transparent Fills, Labels, and Paths
Use fill: 'transparent' for unfilled RoomVisual circles and rectangles, then add debug labels and target paths without confusing visuals with game results.
Screeps Creep.attack(): Melee Range, ATTACK Parts, and Return Codes
Use Creep.attack() with the correct range-1 boundary, active ATTACK parts, documented return codes, Rampart behavior, and later-tick verification.
Screeps Game.notify(): Send Rate-Limited Alerts Safely
Call Game.notify(), use groupInterval and simple Memory incident state to avoid repeated alerts, preserve the checked engine result, and keep scheduling separate from external email delivery.
Screeps processPower(): Energy Ratio, GPL, and Reserves
Recover an owned active Power Spawn, calculate base and PWR_OPERATE_POWER processing amounts, require Power and POWER_SPAWN_ENERGY_RATIO Energy, preserve a configurable room reserve, store GPL and resource snapshots, handle return codes, and verify later deltas.
Screeps Room.getEventLog(): Read Previous-Tick Events
Read the previous tick's Room events, distinguish parsed and raw mode, filter event-specific data safely, match actor and target IDs when attribution matters, and keep optional history bounded.
Screeps Terminal.send(): Prevent Intent Overwrite and Verify Actual Amount
Freeze one transfer revision, reserve the exact Terminal against send and market-deal conflicts, submit once, normalize ledger descriptions, and verify the actual full or partial outgoing transaction next tick.
Screeps CPU Bucket Degradation: Protect Critical Tasks and Recover Gradually
Build a four-mode Screeps CPU degradation scheduler with hysteresis, consecutive-tick confirmation, critical-first task tiers, stable staggering, CPU headroom guards, and gradual recovery.
Publication standard
English articles are published only after source review, official API checks where applicable, JavaScript syntax review where code is present, duplicate-intent and link checks, and editorial review. Publication does not imply Console or multi-tick live-room verification; those evidence states remain separate in each guide. Review the verification method.