| Ecosystem | 1 | 0 |
| Match Graph | 0 | 0 |
| Pricing | Free | Paid |
| Capabilities | 11 decomposed | 14 decomposed |
| Times Matched | 0 | 0 |
Repairs syntactically broken JSON by using ANTLR parser to identify structural errors (missing braces, brackets, parentheses) and applies configurable repair strategies (SimpleRepairStrategy, CorrectRepairStrategy) to fix them. The JSONRepair orchestrator class manages the repair pipeline, attempting fixes iteratively up to a configurable limit, with error context tracking via the Expecting class to understand what tokens are missing at failure points.
Unique: Uses ANTLR-based syntax-aware parsing with strategy pattern for multi-pass repair attempts, rather than regex-based string manipulation; tracks error context via Expecting class to understand what tokens are missing at specific parse failure points, enabling targeted repairs instead of blind string patching
vs alternatives: More structurally aware than regex-based JSON repair tools because it parses the full token stream and understands nesting depth, allowing it to correctly repair complex nested structures where simpler tools would fail or produce invalid output
Extracts valid JSON objects or arrays from larger text blocks (e.g., LLM responses with explanatory text before/after JSON) using SimpleExtractStrategy, which scans for JSON delimiters and isolates contiguous JSON content. Extracted JSON is then passed through the repair pipeline if it contains anomalies, enabling end-to-end recovery of structured data from unstructured LLM outputs.
Unique: Combines extraction (SimpleExtractStrategy) with repair in a single pipeline, so extracted JSON that is malformed is automatically repaired; most tools extract OR repair, not both in sequence
vs alternatives: Handles the full end-to-end workflow of extracting JSON from noisy LLM text and fixing it in one call, whereas regex-based extractors require separate repair steps and often fail on partially-formed JSON
Includes comprehensive integration tests (IntegrationTests class) covering a wide range of JSON anomalies produced by LLMs: missing braces/brackets, unquoted keys/values, trailing commas, missing outer delimiters, and nested structure errors. Tests are organized by anomaly type and include both positive cases (repair succeeds) and negative cases (repair fails gracefully), providing confidence in repair behavior across different LLM output patterns.
Unique: Organizes tests by JSON anomaly type with explicit test cases for each repair strategy, providing clear visibility into what anomalies are handled and which are not; most JSON repair tools lack comprehensive test documentation
vs alternatives: Provides explicit test coverage for different LLM output anomalies, enabling developers to understand repair behavior and limitations before integrating into production systems
Implements a configurable repair pipeline via JSONRepairConfig that allows developers to set maximum repair attempt counts and extraction modes. The JSONRepair orchestrator applies repair strategies iteratively, re-parsing after each fix attempt until either the JSON is valid or the attempt limit is reached. This prevents infinite loops while allowing heuristic-based repairs to converge on valid output through multiple passes.
Unique: Exposes repair attempt limits and extraction mode as first-class configuration parameters via JSONRepairConfig, allowing developers to tune repair behavior without modifying code; most JSON repair tools have fixed repair logic with no tuning surface
vs alternatives: Provides explicit control over repair aggressiveness and resource consumption, whereas most JSON repair libraries apply a fixed set of heuristics with no way to adjust behavior for different LLM output characteristics
Tracks parse error context through the Expecting class, which records what tokens the parser expected at the point of failure (e.g., 'expected }' or 'expected ]'). This error context is used by repair strategies to make targeted fixes rather than blind string manipulation. When ANTLR parsing fails, the Expecting object captures the expected token type and position, enabling the repair strategy to insert the correct missing delimiter at the right location.
Unique: Uses ANTLR error listener integration to capture expected token context at parse failure points, enabling context-aware repairs; most JSON repair tools use simple regex or string-based heuristics without understanding what the parser expected
vs alternatives: Provides semantic understanding of parse failures through token expectations, allowing repairs to be targeted and correct, whereas blind string manipulation approaches often produce invalid JSON or incorrect repairs
Repairs JSON where keys or values lack quotation marks (e.g., {f:v} instead of {"f":"v"}) by detecting unquoted identifiers and automatically inserting quotes around them. This is handled as part of the SimpleRepairStrategy, which identifies tokens that should be strings but lack delimiters and wraps them in quotes during the repair pass.
Unique: Integrates quote insertion into the ANTLR-based repair pipeline, so unquoted keys/values are identified during parsing and fixed in context, rather than using post-hoc regex replacement which can miss edge cases
vs alternatives: More accurate than regex-based quote insertion because it understands JSON structure and nesting, avoiding false positives in edge cases like unquoted values in nested objects
Removes redundant or trailing commas in JSON arrays and objects (e.g., [1,2,] becomes [1,2]) as part of the SimpleRepairStrategy. The repair logic detects comma tokens that appear before closing brackets or braces and removes them, producing valid JSON that conforms to the JSON specification which disallows trailing commas.
Unique: Integrates comma removal into the ANTLR-based repair pipeline with token-level awareness, so commas are removed only when they appear before closing delimiters, avoiding false positives in string values or nested structures
vs alternatives: More precise than regex-based comma removal because it understands JSON token boundaries and nesting, avoiding accidental removal of commas in string values or nested arrays
Automatically adds missing outermost braces or brackets to convert partial JSON fragments into valid JSON objects or arrays. For example, converts [1,2,3 to [1,2,3] or {"key":"value" to {"key":"value"}. This is implemented in SimpleRepairStrategy by detecting unclosed top-level delimiters and inserting the corresponding closing delimiter at the end of the input.
Unique: Detects unclosed top-level delimiters via ANTLR parsing and adds the corresponding closing delimiter, rather than using heuristic string matching; this ensures the added delimiter is correct for the structure type
vs alternatives: More reliable than simple string-based approaches (e.g., appending '}' if input starts with '{') because it understands nesting depth and can correctly close nested structures
+3 more capabilities
Automatically loads and parses documents from diverse sources (PDFs, Word docs, HTML, Markdown, code files, databases) into a unified in-memory representation using format-specific loaders and node-based document abstractions. Each document is decomposed into Document objects containing metadata, content, and relationships, enabling downstream processing without format-specific handling in application code.
Unique: Provides a unified loader abstraction (BaseReader interface) that normalizes 100+ data source connectors into a single Document/Node API, eliminating format-specific branching logic in application code. Loaders are composable and chainable, allowing sequential transformations (e.g., load → split → extract metadata → embed).
vs alternatives: Broader out-of-the-box loader coverage than LangChain's document loaders and more structured node-based decomposition than raw text splitting, reducing boilerplate for multi-source RAG pipelines.
Splits documents into semantically coherent chunks using multiple strategies (character-based, token-aware, recursive, semantic) with configurable overlap and chunk size. Preserves document hierarchy and metadata through a node tree structure, enabling retrieval systems to maintain context relationships and enable hierarchical re-ranking or parent-document retrieval patterns.
Unique: Implements a node-tree abstraction that preserves document hierarchy and enables parent-document retrieval patterns. Supports multiple splitting strategies (recursive, semantic, code-aware) with pluggable custom splitters, and automatically propagates metadata through the node tree.
vs alternatives: More sophisticated than LangChain's text splitters because it preserves hierarchical relationships and supports semantic splitting; better for complex document structures than simple character-based splitting.
LlamaIndex scores higher at 40/100 vs json-repair at 25/100. json-repair leads on adoption and ecosystem, while LlamaIndex is stronger on quality. However, json-repair offers a free tier which may be better for getting started.
Need something different?
Search the match graph →© 2026 Unfragile. Stronger through disorder.
Processes documents containing mixed content (text, images, tables, code) by extracting and understanding each modality separately, then synthesizing information across modalities. Uses vision models for image understanding, specialized parsers for tables and code, and integrates results into a unified document representation for retrieval and generation.
Unique: Integrates vision models, table parsers, and code extractors into a unified multi-modal document processing pipeline that synthesizes information across modalities. Preserves modality-specific structure (table schemas, code formatting) while enabling cross-modal retrieval and generation.
vs alternatives: More comprehensive multi-modal support than text-only RAG; built-in vision integration reduces boilerplate for document understanding compared to manual vision API calls.
Enables streaming of LLM responses token-by-token and real-time retrieval updates, allowing applications to display partial results as they become available. Supports streaming from retrieval (progressive document discovery) and generation (token-by-token output) with backpressure handling and cancellation support for responsive user experiences.
Unique: Provides first-class streaming support for both retrieval and generation with automatic backpressure handling and cancellation. Enables progressive result display without custom async/streaming code in application layer.
vs alternatives: More integrated streaming support than manual LLM API streaming; built-in retrieval streaming and backpressure handling reduce complexity compared to custom streaming implementations.
Tracks API costs for LLM calls, embeddings, and other operations with per-query and per-session cost attribution. Provides cost optimization recommendations (e.g., batch processing, model selection, caching) and enables cost-aware query planning to balance quality and expense. Integrates with multiple LLM providers to normalize cost tracking across models.
Unique: Provides automatic cost tracking across multiple LLM providers with per-query attribution and cost optimization recommendations. Integrates with query execution to enable cost-aware planning without manual cost calculation.
vs alternatives: More integrated cost tracking than manual API billing review; built-in optimization recommendations reduce guesswork for cost reduction.
Enables building custom RAG pipelines by composing modular components (retrievers, synthesizers, agents, tools) through a declarative or programmatic API. Supports complex workflows with branching, loops, and conditional logic, with automatic dependency resolution and execution optimization. Pipelines are reusable, testable, and can be deployed as APIs or batch jobs.
Unique: Provides a flexible pipeline composition API supporting both declarative and programmatic definitions, with automatic dependency resolution and execution optimization. Enables complex workflows with branching and conditional logic without custom orchestration code.
vs alternatives: More flexible pipeline composition than fixed RAG architectures; better workflow support than manual component chaining.
Generates embeddings for documents/nodes using pluggable embedding providers (OpenAI, Hugging Face, local models) and stores them in a unified vector store interface that abstracts over multiple backends (Pinecone, Weaviate, Milvus, FAISS, Chroma, etc.). The abstraction layer enables switching vector stores without changing application code, and handles batching, retry logic, and metadata indexing.
Unique: Provides a unified VectorStore interface that abstracts 10+ vector database backends, enabling zero-code switching between providers. Handles embedding batching, retry logic, and metadata propagation automatically. Supports both cloud and local embedding models through a pluggable EmbedModel interface.
vs alternatives: Broader vector store coverage and more seamless provider switching than LangChain's vectorstore integrations; better abstraction consistency across backends than using raw vector store SDKs directly.
Retrieves semantically similar documents from vector stores using embedding-based similarity search, with optional re-ranking, filtering, and fusion strategies (hybrid search combining dense and sparse retrieval). Supports multiple retrieval modes (similarity, MMR, fusion) and enables custom retrieval logic through a pluggable Retriever interface that can combine multiple strategies.
Unique: Implements a pluggable Retriever abstraction supporting multiple retrieval strategies (similarity, MMR, fusion, custom) that can be composed and chained. Built-in support for re-ranking via LLM or cross-encoder, and hybrid search combining dense and sparse retrieval without custom integration code.
vs alternatives: More flexible retrieval composition than LangChain's retrievers; built-in re-ranking and fusion strategies reduce boilerplate for advanced retrieval pipelines.
+6 more capabilities