SEARCH + DIAGNOSTICS
Search discovers the most relevant guides, references, return codes, and tools. When the answer is still uncertain, continue through symptom diagnostics, API surfaces, and accepted Runtime Evidence.
Problem → likely cause → return code / API → guide / tool → accepted Runtime Evidence.
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80 matching results
When boostCreep() appears to fail, capture the real return value first, then separate ownership, eligible parts, Lab resources, target validity, range, and RCL; after OK, verify body boosts and Lab Store changes on a later tick.
Screeps API surface: lab.boostCreep(creep, bodyPartsCount?).
Screeps API surface: lab.runReaction(inputLab1, inputLab2).
Screeps API surface: spawn.recycleCreep(creep).
Screeps API surface: spawn.spawnCreep(body, name, opts?).
A focused hub for Creep movement, harvesting, hauling, Controller upgrading, return codes, guides, and tools.
A focused hub for Lab reactions, Boosts, mineral and Energy prerequisites, cooldown, and production planning.
Learn StructureLab.boostCreep() requirements, bodyPartsCount usage, return codes, current-tick scheduling, and how to verify exact boosted body parts afterward.
Search common Game, Creep, Room, Structure, Market, and PathFinder APIs and continue to matching guides or official documentation.
High-frequency Screeps error codes with diagnostic paths into APIs, object hubs, guides, tools, and runtime verification.
Use fill: 'transparent' for unfilled RoomVisual circles and rectangles, then add debug labels and target paths without confusing visuals with game results.
Start from visible symptoms such as a Creep not moving, Spawn failures, Controller downgrade pressure, Link transfer problems, Market failures, high CPU, or stalled logistics, then continue into return codes, APIs, object hubs, guides, tools, and runtime verification.
Learn what Screeps is, how JavaScript controls its persistent world, and how Rooms, Creeps, Sources, Spawns, and Controllers work together for new players.
Choose between getRangeTo(), inRangeTo(), isNearTo(), isEqualTo(), findClosestByRange(), findClosestByPath(), and findInRange() without confusing linear range with route reachability.
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.
Catch JavaScript exceptions at room or subsystem boundaries, retain bounded rate-limited evidence, pause repeatedly failing optional work, and retry after cooldown without confusing API return codes or CPU termination with exceptions.
Bind one request to three exact Lab IDs, snapshot both reagent types and Stores, submit once, and verify the product and two reagent deltas under an exclusive action window.
Diagnose room.energyAvailable below energyCapacityAvailable by reconciling active Spawn and Extension Stores, holding one stable fill target, preserving transfer() results, and matching the processed Energy transfer on the next tick.
Plan compound reaction chains, base minerals, Lab runs, production ticks, and Boost batches.
Bind the Claimer and Controller IDs, record only accepted reserve or claim calls, verify reserve events without inventing a targetId, and verify claims through exact next-tick ownership.
Distinguish local variables, disposable heap cache, and persistent Memory; initialize Creep state safely; store JSON-compatible values; and recover current game objects from IDs.
Find injured owned Creeps, rank lower hit ratios before missing hits and nearest-Tower range, require active owned Towers with TOWER_ENERGY_COST, save heal() results, avoid caching stale targets, and leave over-heal optimization to a later dispatcher.
Publish versioned public RawMemory segments, request one foreign segment for the next tick, validate untrusted JSON, rotate subscriptions, and detect stream changes without confusing local, cross-shard, and foreign storage.
Meaningful changes to the English interface, navigation, search, tools, accessibility, and technical SEO.
Distinguish general, limited, and read-only Stores; interpret resource arguments, zero and null correctly; handle Lab and specialized capacities; and calculate safe withdraw and transfer amounts.
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.
Validate one fixed anchor against Controller range 3 and Link range 1, recover the exact owned Controller Link, diagnose Energy and active body parts, preserve move, withdraw, and upgrade return codes, and verify later position, Store, or event evidence.
Topic archives for Memory, spawning, Creeps, Energy, movement, pathfinding, Controllers, construction, defense, market systems, resources, CPU, debugging, and JavaScript.
Completed work, next improvements, evidence-dependent tasks, tool development, accessibility, and performance checks.
Save an ID with room and kind metadata, return explicit invalid, no-vision, missing, wrong-type, and ready states, and keep restoration separate from reselection and actions.
Capture the actual Spawn request, interpret each documented return code, separate dryRun from the final submission, and verify scheduled spawning across later ticks.
Verify movement over later ticks, then isolate fatigue, repeated movement intents, traffic, cached paths, room edges, and impossible stop ranges.
Separate ERR_NO_PATH from missing cached paths and incomplete PathFinder searches, then inspect goal range, CostMatrix rules, callbacks, limits, and room routes.
Separate room planning from exit-tile pathfinding, validate the first route step, use finite risk costs versus hard bans, and verify the border transition on later ticks.
Collect requests, choose one target per Observer, make one final observeRoom() call, store only that accepted target, read it next tick, and keep visibility attribution honest.
In Screeps PathFinder, a CostMatrix cost of 255 is unwalkable. See what 0, 1–254, and 255 mean, plus practical road, obstacle, and roomCallback rules.
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.
Freeze one reviewed order revision, reserve the creation fee and account mutation slot, call createOrder once, and verify the exact new order ID in the next account snapshot.
Freeze one reviewed deal revision, reserve both an account deal slot and the exact Terminal, submit once, and verify the new transaction ID and actual partial or full amount next tick.
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.
Route every Safe Mode request through one final per-tick dispatcher, bind the exact Controller ID, disable the request before activateSafeMode(), and verify activation consumption on the next tick.
Bind one reviewed boolean change to the exact Rampart, reserve that ID for the tick, record pending evidence only after OK, and verify the same object's isPublic state on the next tick.
Change, extend, or cancel one owned Screeps market order with nullable room fingerprints, conservative fee budgeting, one-writer request IDs, raw return codes, and next-tick state verification.
Browse 12 published English guides related to Rooms.
Browse 17 published English guides related to Resources.
A focused hub for room visibility, Construction Sites, Event Log, and room-level diagnostics.
See which high-frequency diagnostic paths have accepted Console or live multi-tick verification, what evidence is missing, and which runtime checks should come next.
Browser-based body, room, Market, Controller, Lab, Spawn, hauling, and Tower tools that do not request a Screeps token or connect to an account.
Project purpose, verification approach, evidence boundaries, public development history, repository, and contact information.
Open a Screeps Room, switch to the code editor and player Console, then use read-only checks to match exact Room, Spawn, Creep, Source, and Controller data.
Combine three fixed beginner roles in one small loop, submit one validated Spawn request, keep Energy phases stable, expose failure statuses, and verify accepted commands on later ticks.
Enter acquire at zero Energy, enter work when full, preserve the previous phase at partial values, initialize explicitly, and keep state selection separate from actions and outcomes.
Separate minimum, target, and emergency body policies; scale one role template within current Energy and the 50-part limit; then validate spawning separately.
Find the action that returned ERR_NOT_IN_RANGE, use its documented range, submit movement separately, and retry the action on a later tick.
Calculate unboosted Creep movement from MOVE recovery, loaded body weight, road, plain, and swamp costs; account for empty CARRY parts; and separate a static body estimate from live multi-tick movement proof.
Measure one code section with Game.cpu.getUsed() deltas, compare equivalent server ticks, separate bucket context from profiling, and protect essential work before optional tasks.
Request active Segment IDs once, read them on a later tick, distinguish unavailable from empty, validate versioned JSON, and write only after a successful read.
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.
Separate permanent Factory level from the active Power effect, snapshot every recipe component, submit one batch, and verify exact output and component deltas under an exclusive Store window.
Validate the same-tile Extractor and Miner, record only accepted harvest calls, match the exact EVENT_HARVEST on the next tick, and separate event identity from Store overflow and depletion.
Coordinate one shared Storage withdrawal budget and target capacity map, record only accepted withdraw or transfer calls, and verify the exact source-target event on the next tick.
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.
Resolve an exact Flag, validate its schema, bind saved object IDs to the Flag room and expected type, make fallback an explicit policy, and report configuration drift without mutating the Flag.
Call PathFinder.search() with the goal range your action actually needs, interpret path, ops, cost, and incomplete correctly, and reject partial paths before handing movement to a Creep.
Coordinate Creep.pull(), the puller's movement, and target.move(puller) in the same tick, handle adjacency and fatigue correctly, and verify the pair moved later.
Calculate CARRY payload, MOVE fatigue, route cycle time, Creeps required, lifetime delivery, and replacement timing.
Current boundaries for reusing site content, code examples, third-party names, and commercial material.
Use Creep.harvest() to find an active Source, move into range, keep harvesting until your Creep is ready to deliver, and read Source-specific return codes without treating ERR_FULL as a harvest result.
Make one Creep transfer Energy to a named Spawn, keep delivery mode until it is empty, and connect harvesting and delivery into a first repeatable round trip.
Inspect one Creep's active WORK, CARRY, and MOVE parts, then use its action result, Store, fatigue, and damage to diagnose missing abilities.
Give Builder1 a clear priority: build owned sites, repair selected damaged structures, and upgrade the Controller when no higher task exists.
Inspect a misplaced Construction Site, validate its identity, submit remove() once, handle return codes, and verify the result on the next tick.
Find a Container that currently holds Energy, check the Creep's free capacity, call withdraw(), handle range and return codes, and keep the delivery task outside this focused guide.
Detect whether a capable harvester exists or is already spawning, submit one minimum recovery request, save the exact Spawn and Creep name, and verify that request across later ticks.
Cache derived IDs and plain data in global, rebuild after resets, invalidate with explicit versions, and keep callers correct when the cache is missing or stale.
Enter Controller recovery with hysteresis, reject blocked or unready attempts, submit one upgrader action, and verify the exact Creep in the next tick's room event log.
Use a one-time Memory request, validate a visible room and 0–49 coordinates, allow Road placement on natural wall terrain, reject an existing Road or Construction Site, respect MAX_CONSTRUCTION_SITES, disable before createConstructionSite(), and verify later.
Bind confirmation to the exact Extension and owned room, block hostile Creeps and Power Creeps, submit one queued destroy call, then distinguish original-ID removal from a later replacement at the tile.
Keep one main loop, export small functions, pass current game objects into modules, validate role contracts once per runtime, isolate per-Creep failures, and keep durable state out of module scope.
Bind confirmation to the exact Nuker and target, record only an accepted launch, verify the launcher's zeroed resources and cooldown, and match the exact Nuke object when target vision exists.