ErrLookup › Unity-Technologies/ml-agents
Unity-Technologies/ml-agents
The Unity Machine Learning Agents Toolkit (ML-Agents) is an open-source project that enables games and simulations to serve as environments for training intelligent agents using deep reinforcement learning and imitation learning. · C# · 481 source files
Analyzed at 3ecb446f75 on 2026-09-02. 143 documented errors.
| Code / Message | Type | Severity | Tags |
|---|---|---|---|
| Demonstration import error. | exception | error | unity, editor, asset-import, demonstration |
| Index out of bounds, expected a number between 0 and {Length | exception | error | unity, ml-agents, index-out-of-range, actions |
| Enumerator not started. | exception | error | unity, ml-agents, enumerator, invalid-operation |
| Enumerator has reached the end already. | exception | error | unity, ml-agents, enumerator, invalid-operation |
| Action spaces with both continuous and discrete actions are | exception | error | unity, ml-agents, action-space, configuration |
| Call to SendInfoToBrain when Agent hasn't been initialized.P | exception | error | unity, ml-agents, agent, initialization-order |
| Agent is already registered with a group. Unregister it firs | exception | error | unity, ml-agents, agent, group-management |
| The number of training areas that you have specified exceeds | exception | error | unity, ml-agents, training-area, configuration |
| API versions of demonstration are incompatible. | exception | error | unity, ml-agents, demonstration, version-mismatch |
| GetCompressedObservation() returned null data for sensor nam | exception | error | unity, ml-agents, sensor, compression, null-reference |
| Variable Length Observations are not supported by the traine | exception | error | unity, ml-agents, trainer-compatibility, observation, version-mismatch |
| {failedCheck.Message} | exception | error | unity, ml-agents, sentis, model-validation, shape-mismatch |
| Unknown tensorProxy expected as output : {tensor.name} | exception | error | unity, ml-agents, inference, tensor, naming-mismatch |
| Sensor {sensor.GetName()} have an invalid rank {rank} | exception | error | unity, ml-agents, inference, sensor, rank, observation-shape |
| Unknown tensorProxy expected as input : {tensor.name} | exception | error | unity, ml-agents, inference, tensor, naming-mismatch |
| Only float data types are currently supported | exception | error | unity, ml-agents, tensor, dtype, not-implemented |
| row was {row}, but must be between 0 and {maxBoardSize.Rows | exception | error | unity, ml-agents, match3, index-out-of-range, bounds |
| col was {col}, but must be between 0 and {maxBoardSize.Colum | exception | error | unity, ml-agents, match3, index-out-of-range, bounds |
| Cannot move cell at row={row} col={col} in Direction={dir} | exception | error | unity, ml-agents, match3, index-out-of-range, edge-move, bounds |
| Can't use Behavior Type {behaviorType} without a model. Eith | exception | critical | unity, ml-agents, configuration, inference |
| {m_MethodName} called recursively. This might happen if you | exception | critical | unity, ml-agents, recursion, environment-step |
| The BufferSensor was expecting an observation of size {m_Obs | exception | error | unity, ml-agents, sensors, buffer-sensor, shape-mismatch |
| GridSensor only supports 2D grids. | exception | error | unity, ml-agents, grid-sensor, configuration |
| When using compression type {m_CompressionType} the data val | exception | error | unity, ml-agents, grid-sensor, normalization, compression |
| GridSensorComponent received no sensors. Specify at least on | exception | error | unity, ml-agents, grid-sensor, configuration, empty-list |
| shape and dimensionProperties must have the same length. | validation | error | unity, ml-agents, observation-spec, shape-mismatch, api-misuse |
| height value {h} must be in range [0, {m_TensorShape.Height( | validation | error | unity, ml-agents, observation-writer, bounds, index-out-of-range |
| width value {w} must be in range [0, {m_TensorShape.Width() | validation | error | unity, ml-agents, observation-writer, bounds, index-out-of-range |
| channel value {ch} must be in range [0, {m_TensorShape.Chann | validation | error | unity, ml-agents, observation-writer, bounds, index-out-of-range |
| No parent indices set | exception | error | unity, ml-agents, null-reference, sensor, initialization-order |
| Expected parentIndices[0] to be -1, got {parentIndices[0]} | validation | error | unity, ml-agents, validation, hierarchy, debug-assert |
| A side channel with id {channelId} is already registered. Yo | exception | error | unity, ml-agents, side-channel, duplicate-registration, guid |
| There was a problem reading a message in a SideChannel. Plea | exception | error | unity, python, ml-agents, side-channel, version-mismatch, serialization |
| StatsSideChannel should never receive messages. | exception | error | unity, python, ml-agents, side-channel, contract-violation, stats |
| agent_id {agent_id} is not present in the DecisionSteps | exception | error | python, ml-agents, keyerror, decision-steps, agent-lifecycle |
| agent_id {agent_id} is not present in the TerminalSteps | exception | error | python, ml-agents, keyerror, terminal-steps, agent-lifecycle |
| The behavior {name} needs a continuous input of dimension {_ | validation | error | python, ml-agents, action-space, shape-mismatch, validation |
| The behavior {name} needs a discrete input of dimension {_ex | validation | error | python, ml-agents, action-space, shape-mismatch, discrete-actions |
| Couldn't launch the {file_name} environment. Provided filena | exception | error | python, ml-agents, environment-launch, file-not-found, executable |
| Error when trying to launch environment - make sure permissi | exception | error | permissions, subprocess, environment-launch |
| The communication API version is not compatible between Unit | exception | error | version-mismatch, protocol, ml-agents |
| If the environment name is None, the worker-id must be 0 in | exception | error | configuration, editor-connection, worker-id |
| Communicator has exited. | exception | error | environment-crashed, communicator, process-exited |
| No Unity environment is loaded. | exception | error | lifecycle, environment, reset |
| The group {behavior_name} does not correspond to an existing | exception | error | behavior-name, agent-group, validation |
| agent_id {} is did not request a decision at the previous st | exception | error | agent-id, decision-steps, validation |
| There can only be one behavior in a UnityEnvironment if it i | exception | error | gym, unity-environment, configuration |
| There are no observations provided by the environment. | exception | error | gym, unity-environment, observations |
| The gym wrapper does not provide explicit support for both d | exception | error | gym, action-space, unity-environment |
| You are calling 'step()' even though this environment has al | exception | error | gym, episode-lifecycle, api-misuse |
| There can only be one Agent in the environment but {n_agents | exception | error | gym, unity-environment, single-agent |
| The make() method not implemented for entry {self.identifier | exception | error | registry, abstract-method, python |
| Binary not found, make sure {url} is a valid url to a zip fo | exception | error | download, file-not-found, registry |
| No extensions found for this platform. | exception | error | platform, registry, unsupported |
| The entry {self.identifier} does not contain a valid url for | exception | error | registry, platform, file-not-found |
| The entry {identifier} is not present in the registry. | exception | error | registry, keyerror, python |
| Couldn't start socket communication because worker number {} | exception | error | python, unity-ml-agents, port-in-use, network |
| The Unity environment took too long to respond. Make sure th | exception | error | python, unity-ml-agents, timeout, grpc |
| Compressed observation and its mapping had different number | exception | error | python, unity-ml-agents, observation, protocol-mismatch |
| Invalid Compressed Channel Mapping: the mapping {mappings} d | exception | error | python, unity-ml-agents, observation, protocol-mismatch |
| Invalid Compressed Channel Mapping: the mapping has index la | exception | error | python, unity-ml-agents, observation, protocol-mismatch |
| Observation at index={obs_index} for agent with id={agent_in | exception | error | python, unity-ml-agents, observation, shape-mismatch |
| Observation did not have the expected shape - got {obs.shape | exception | error | python, unity-ml-agents, observation, shape-mismatch |
| Decompressed observation did not have the expected shape - d | exception | error | python, unity-ml-agents, observation, compression, shape-mismatch |
| The {source} provided had NaN values. | exception | error | python, unity-ml-agents, nan, numerical |
| The {source} provided had Infinite values. | exception | error | python, unity-ml-agents, infinity, numerical |
| The DefaultTrainingAnalyticsSideChannel received a message f | exception | error | unity, side-channel, version-mismatch |
| The EngineConfigurationChannel received a message from Unity | exception | error | unity, side-channel, version-mismatch |
| You cannot set the width/height of the screen resolution wit | exception | error | configuration, validation, arguments |
| The EnvironmentParametersChannel received a message from Uni | exception | error | unity, side-channel, version-mismatch |
| There was a problem reading a message in a SideChannel. Plea | exception | error | unity, side-channel, version-mismatch, protocol |
| The message received by the side channel {} was unexpectedly | exception | error | unity, side-channel, protocol, version-mismatch |
| There cannot be two side channels with the same channel id { | exception | error | configuration, side-channel, duplicate-id |
| Unknown StatsAggregationMethod encountered. {agg_type} | exception | error | trainer, stats, version-mismatch |
| The batch size and training length requested for get_batch w | exception | error | training, buffer, rl, hyperparameters |
| {key} has type ({type(key0)}, {type(key1)}) | exception | error | keyerror, type-mismatch, ml-agents, buffer |
| {key} is a {type(key)} | exception | error | keyerror, type-mismatch, ml-agents, buffer |
| Unable to convert {encoded_key} to an AgentBufferKey | exception | error | valueerror, deserialization, ml-agents, buffer |
| Unable to shuffle if the fields are not of same length | exception | error | bufferexception, ml-agents, buffer, data-integrity |
| The length of the fields {key_list} were not of same length | exception | error | bufferexception, ml-agents, buffer, data-integrity |
| Config file could not be found at {abs_path}. | exception | error | config, file-not-found, ml-agents, cli |
| There was an error decoding Config file from {config_path}. | exception | error | config, encoding, utf-8, ml-agents, yaml |
| Error parsing yaml file. Please check for formatting errors. | exception | error | config, yaml, parse-error, ml-agents |
| The actions {} in demonstration do not match the policy's {} | exception | error | runtimeerror, ml-agents, demonstrations, action-space-mismatch |
| The demonstrations do not have the same number of observatio | exception | error | ml-agents, demonstrations, observation-mismatch, imitation-learning |
| The shape {demo_obs} for observation {i} in demonstration | exception | error | ml-agents, demonstrations, shape-mismatch, imitation-learning |
| The path provided is not a '.demo' file. | exception | error | ml-agents, file-path, demonstrations, valueerror |
| There are no '.demo' files in the provided directory. | exception | error | ml-agents, file-path, demonstrations, empty-directory |
| The demonstration file or directory {path} does not exist. | exception | error | ml-agents, file-path, demonstrations, file-not-found |
| Can't load Demonstration data from an unsupported version ({ | exception | error | ml-agents, demonstrations, version-incompatibility, serialization |
| No BrainParameters found in demonstration file at {file_path | exception | error | ml-agents, demonstrations, corrupt-file, serialization |
| Previous data from this run ID was found. Either specify a n | exception | error | ml-agents, trainer, output-directory, run-id |
| Previous data from this run ID was not found. Train a new ru | exception | error | ml-agents, trainer, resume, run-id |
| Could not initialize from {init_file}. file does not exists | exception | error | ml-agents, file-not-found, checkpoint-loading, configuration |
| Registering Object of unsupported type {} to ModelSaver | exception | error | ml-agents, type-error, pytorch, api-misuse |
| Continuous NaN action detected. | exception | critical | ml-agents, nan, numerical-instability, training-divergence |
| SAC does not support SharedActorCritic | exception | error | ml-agents, configuration, sac, incompatible-options |
| Inf found | exception | critical | ml-agents, sac, nan, inf, training-divergence |
| The option {key} was specified in your YAML file for {class_ | validation | error | ml-agents, configuration, yaml, schema-validation, typo |
| Unsupported config {d} for {t.__name__}. | validation | error | ml-agents, configuration, yaml, schema-validation, type-error |
| When using a recurrent network, memory size must be greater | validation | error | ml-agents, configuration, validation, lstm, yaml |
| When using a recurrent network, memory size must be divisibl | validation | error | config, recurrent-network, lstm, validation |
| Unsupported reward signal configuration {d}. | validation | error | config, yaml, reward-signals, validation |
| __str__ not implemented for type {self.__class__}. | exception | warning | api-misuse, parameter-randomization, string-formatting |
| Unsupported parameter randomization configuration {d}. | validation | error | config, yaml, parameter-randomization, validation |
| Sampler configuration does not contain sampler_type : {d}. | validation | error | config, yaml, parameter-randomization, missing-key |
| Sampler configuration does not contain sampler_parameters : | validation | error | config, yaml, parameter-randomization, missing-key |
| Minimum value is greater than maximum value in uniform sampl | validation | error | config, validation, sampler, parameter-randomization |
| The sampling interval {interval} must contain exactly two va | validation | error | config, validation, sampler, parameter-randomization |
| Minimum value is greater than maximum value in interval {int | validation | error | config, validation, sampler, parameter-randomization |
| Threshold for next lesson cannot be greater than 1 when the | validation | error | config, curriculum, validation, lessons |
| Threshold for next lesson cannot be negative when the measur | validation | error | config, curriculum, ml-agents |
| A non-terminal lesson does not have a completion_criteria fo | validation | error | config, curriculum, ml-agents |
| Unsupported parameter environment parameter settings {d}. | validation | error | config, deserialization, ml-agents |
| When using memory, sequence length must be less than or equa | validation | error | config, validation, ml-agents |
| Hyperparameters were specified but no trainer_type was given | validation | error | config, ml-agents |
| Settings for trainer type {d_copy['trainer_type']} were not | validation | error | config, ml-agents |
| Invalid trainer type {val} was found | validation | error | config, ml-agents |
| The behavior name {key} has not been specified in the traine | validation | error | config, ml-agents |
| num_envs must be 1 if env_path is not set. | validation | error | config, environment, ml-agents |
| num_areas must be set to a positive number >= 1. | validation | error | |
| The option {} was specified in your YAML file, but is invali | validation | error | |
| UnityEnvironment worker: send failed. | exception | error | |
| UnityEnvironment worker: recv failed. | exception | error | |
| Workers {still_waiting} stuck in waiting state | exception | error | |
| Trying to export an attention mechanism that doesn't have a | exception | error | |
| The reward provider's evaluate method has not been implement | exception | error | |
| The reward provider's update method has not been implemented | exception | error | |
| Unknown reward signal type {name} | exception | error | |
| The trainer was unable to process any of the provided inputs | exception | error | python, mlagents, configuration, sensors |
| The one of the goals uses variable length observations. This | exception | error | python, mlagents, unsupported-feature, entity-embeddings |
| Trainer was unable to process any of the goals provided as i | exception | error | python, mlagents, configuration, empty-input |
| The schedule {self.schedule} is invalid. | exception | error | python, mlagents, config-validation, hyperparameters |
| Visual observation resolution ({width}x{height}) is too smal | exception | error | python, mlagents, visual-observations, resolution, config |
| Unsupported Sensor with specs {obs_spec} | exception | error | python, mlagents, observations, unsupported-sensor |
| NotImplementedError | exception | error | python, mlagents, abstract-method, custom-trainer |
| The trainer config contains an unknown trainer type {trainer | exception | error | python, mlagents, config-validation, trainer-type |
| The folder {output_path} containing the generated model coul | exception | error | python, mlagents, filesystem, permissions, output-path |
| The TrainingAnalyticsSideChannel received a message from Uni | exception | error | python, mlagents, side-channel, version-mismatch, communication |
| Metadata not found, resuming from an incompatible version of | exception | error | python, ml-agents, resume, checkpoint-incompatible |
| Config doesn't specify a trainer type. Please specify traine | exception | error | python, ml-agents, config, yaml, trainer-type |
| Config doesn't specify use_recurrent. Please specify true or | exception | error | python, ml-agents, config, yaml, use-recurrent |
| Your final lesson definition contains completion_criteria fo | console | warning | python, ml-agents, curriculum, lesson, config-warning |