{"id":23029,"library":"allennlp","title":"AllenNLP","description":"An open-source NLP research library built on PyTorch, providing flexible abstractions for building and training deep learning models. Current version is 2.10.1 (stable, maintenance mode). Release cadence: irregular, with minor releases every few months.","status":"maintenance","version":"2.10.1","language":"python","source_language":"en","source_url":"https://github.com/allenai/allennlp","tags":["nlp","pytorch","research","deep-learning","allenai"],"install":[{"cmd":"pip install allennlp","lang":"bash","label":"pip"},{"cmd":"pip install allennlp[all]","lang":"bash","label":"with extras (cuda, etc.)"}],"dependencies":[{"reason":"Core dependency; AllenNLP is built on PyTorch. Must be installed separately or via allennlp[all].","package":"torch","optional":false},{"reason":"Used for pretrained transformer models (e.g., BERT). Required for many common use cases.","package":"transformers","optional":true},{"reason":"Used for dataset caching. Errors may occur if version mismatch.","package":"cached-path","optional":false}],"imports":[{"note":"Top-level import does not expose common classes directly.","wrong":"import allennlp","symbol":"AllenNLP","correct":"from allennlp.models import Model"},{"note":"Predictor is in the predictors submodule.","wrong":"from allennlp import Predictor","symbol":"Predictor","correct":"from allennlp.predictors import Predictor"},{"note":"DatasetReader is a base class; concrete readers are under allennlp.data.dataset_readers.","wrong":"from allennlp.dataset_readers import DatasetReader","symbol":"DatasetReader","correct":"from allennlp.data import DatasetReader"}],"quickstart":{"code":"import torch\nfrom allennlp.common import JsonDict\nfrom allennlp.data import Instance\nfrom allennlp.data.fields import TextField\nfrom allennlp.data.token_indexers import SingleIdTokenIndexer\nfrom allennlp.data.tokenizers import SpacyTokenizer\nfrom allennlp.models import Model\nfrom allennlp.modules.text_field_embedders import BasicTextFieldEmbedder\nfrom allennlp.modules.token_embedders import Embedding\nfrom allennlp.nn import util\n\n# Example: simple text classifier (not runnable without training data)\nclass SimpleClassifier(Model):\n    def __init__(self, vocab, embed_dim=10):\n        super().__init__(vocab)\n        self.embedder = BasicTextFieldEmbedder({\"tokens\": Embedding(embedding_dim=embed_dim, num_embeddings=vocab.get_vocab_size('tokens'))})\n        self.linear = torch.nn.Linear(embed_dim, vocab.get_vocab_size('labels'))\n\n    def forward(self, text, label=None):\n        embedded = self.embedder(text)\n        logits = self.linear(embedded)\n        output = {\"logits\": logits}\n        if label is not None:\n            output[\"loss\"] = torch.nn.functional.cross_entropy(logits, label)\n        return output\n\nprint(\"AllenNLP ready.\")","lang":"python","description":"Minimal model example demonstrating class structure and forward pass."},"warnings":[{"fix":"Migrate to new API (see migration guide: https://github.com/allenai/allennlp/blob/main/CHANGELOG.md)","message":"AllenNLP 2.0+ removed the old 'allennlp.commands' and many APIs changed. Projects using AllenNLP <1.x will not work.","severity":"breaking","affected_versions":">=2.0"},{"fix":"Inherit from 'allennlp.data.dataset_readers.DatasetReader' instead.","message":"The 'allennlp.data.DatasetReader' abstract class is being phased out in favor of 'allennlp.data.dataset_readers' concrete classes. Custom readers may need updates.","severity":"deprecated","affected_versions":">=2.5"},{"fix":"Install PyTorch first from pytorch.org, then pip install allennlp (without torch dependency).","message":"Installing allennlp from pip may pull incompatible PyTorch versions. Always ensure torch matches your system.","severity":"gotcha","affected_versions":"all"}],"env_vars":null,"last_verified":"2026-05-01T00:00:00.000Z","next_check":"2026-07-30T00:00:00.000Z","problems":[{"fix":"Use correct import path: e.g., 'from allennlp.common import JsonDict'. Ensure package installed: pip install allennlp.","cause":"Importing from incorrect package path or missing installation.","error":"ModuleNotFoundError: No module named 'allennlp.common'"},{"fix":"Use 'model = model.cuda()' or 'model.to(device)' before training, and ensure tensors are moved similarly.","cause":"Moving model/data between CPU and GPU incorrectly.","error":"RuntimeError: Expected all tensors to be on the same device, but found at least two devices"},{"fix":"Use 'from allennlp.models import Model' instead.","cause":"Outdated import style from pre-2.0 versions.","error":"ImportError: cannot import name 'AllenNlpModel' from 'allennlp.models'"},{"fix":"Use 'allennlp.data.DataLoader' and 'allennlp.data.Vocabulary' directly (see updated examples).","cause":"Using deprecated dataset API.","error":"AttributeError: 'AllennlpDataset' object has no attribute 'to_torch_dataset'"}],"ecosystem":"pypi","meta_description":null,"install_score":null,"install_tag":null,"quickstart_score":null,"quickstart_tag":null}