A Python library for parallel LLM inference across providers, built on Polars DataFrames.
Polar Llama is a Python library that enables parallel inference calls to multiple Large Language Model providers through Polars dataframes. It streamlines batch processing of AI queries without serial request delays, making it ideal for data-intensive AI applications. 0.7.2 adds survey data-quality flags: graded straightlining, gibberish, duplicate, length, and speeder scores, with an opt-in LLM tier.
Send multiple inference requests in parallel without waiting for individual completions
OpenAI, Anthropic, Gemini, Groq, AWS Bedrock, and on-device MLX (Apple Silicon)
Dataframe-native tool calling: emission, batch-parallel execution, and synthesis are all ordinary columns
Qualitative and survey research tooling: codebook induction, inter-rater reliability, survey quality flags
Pulls in mlx and mlx-lm; requires an Apple Silicon Mac and Python ≥ 3.10
Get started with a simple example
quality_report(df, QualityConfig(...)) (#80)
Score every respondent in a survey DataFrame for common data-quality problems and get a per-flag summary back, without ever dropping a row. Every score is a graded Float64 in [0, 1] (higher = more suspicious). Booleans come from thresholding, and a null score (not enough signal) always resolves to flag = False.
| Score | Tier | Default threshold | Signal |
|---|---|---|---|
| straightlining_score | Heuristic (Rust) | 0.85 | Mode share vs. normalized variance across a Likert grid |
| gibberish_score | Heuristic (Rust) | 0.65 | Consonant runs, vowel-ratio deviation, and bigram entropy; English-only, so non-Latin text scores null |
| duplicate_answer_score | Heuristic (Rust) | 0.8 | The same answer repeated across a respondent's open-ends |
| response_length_score | Heuristic (Polars) | |robust z| ≥ 3 | Robust z-score of answer length |
| speeder_score | Heuristic (Polars) | 5th percentile | Completion time, by percentile or median fraction |
| near_duplicate | Embedding/LLM (opt-in) | 0.97 | Cross-respondent near-duplicates via embedding_async + knn_hnsw + cosine_similarity |
| likely_ai | Embedding/LLM (opt-in) | 0.75 | Stylistic heuristic via inference_messages(..., response_model=...); also standalone as ai_likelihood |
QualityConfig(llm_tier=True) turns on the embedding/LLM tier. It is off by default, so there are zero network calls unless you ask for them. result.df gains a quality struct column (sub-structs for unconfigured inputs are omitted, not null-filled), and result.summary has one row per active flag plus a final any_flag row. The heuristic scores also work standalone and on the namespace, for example pl.col("g1").llama.straightlining_score([...]).
Documented limitations and tunable thresholds
likely_ai carries a mandatory limitation: AI-text detectors have documented false-positive risk, including bias against non-native English speakers, and the flag must never be the sole grounds for excluding a respondent or sanctioning a panelist. Every default threshold is a documented, subjective convention rather than a validated cutoff, so tune them to your own panel (see docs/QUALITY_FLAGS.md).
0.7.2 is cumulative: every feature shipped in 0.2.2 is still here, plus everything added across 0.3.0, 0.5.0, 0.5.1, 0.5.2, 0.5.3, 0.6.0, 0.6.1, 0.6.2, 0.6.3, 0.7.0, 0.7.1.
Released 2026-06-10 to 2026-07-12
tools_to_response_model, mcp_tools, execute_tool_calls, tool_results_to_message: batch-parallel tool calling over an MCP server or a Python executor (0.3.0)
cache=True / CacheConfig shares a cached system prefix across rows via Anthropic cache_control, with 5-minute and 1-hour TTLs (0.3.0)
Signature, Predict, evaluate, BootstrapFewShot, InstructionOptimizer: DSPy-style instruction and few-shot tuning (0.3.0)
inference_local with server and in_process engines, collapsed prefix prefill, batched quantized KV cache (0.5.0), and an on-device prompt-tuning bridge (0.5.1)
Along the way: updated default models for every provider, OPENAI_BASE_URL / ANTHROPIC_BASE_URL overrides and POLAR_LLAMA_MAX_CONCURRENCY (0.3.0), and fixes for in-process Gemma 3n inference (0.5.2). See the 0.5.2 docs for the full details.
Released 2026-07-13
tag_taxonomy() works on OpenAI strict mode again. The per-field thinking reasoning is now List[{value, reasoning}] instead of a dict keyed by value name, and $ref sibling keywords are stripped from generated schemas (#51). A new warning flags Dict-typed fields in user-supplied response models.
Streaming, checkpointing, usage accounting, and response caching. Released 2026-07-13 to 2026-07-14
| Release | Feature | What shipped |
|---|---|---|
| 0.6.0 | Streaming | inference_stream() with an on_token(row_index, delta) callback and a Struct{text, finished} column; native SSE for OpenAI, Groq, Anthropic; GROQ_BASE_URL override |
| 0.6.1 | Checkpointing | checkpoint="path" / Checkpoint(...) on inference_async and inference_messages: resumable runs over a crash-durable Parquet store keyed by content + config hash |
| 0.6.2 | Usage & cost | usage=True returns Struct{response, usage{input_tokens, output_tokens, cached_tokens, latency_ms, cost_usd}} from an overridable price table (price_table=, register_model_price) |
| 0.6.3 | Dedupe & response cache | dedupe=True collapses duplicate rows in-run; response_cache= / ResponseCache(path, ttl=...) reuses results across jobs; DedupeStats reports hits and calls |
Released 2026-07-14
| Release | Feature | What shipped |
|---|---|---|
| 0.7.0 | Codebook induction | cluster_embeddings (hand-rolled spherical k-means in Rust), induce_codebook, apply_codebook, codebook_to_taxonomy |
| 0.7.1 | Inter-rater reliability | cohens_kappa and krippendorffs_alpha as aggregation expressions, bit-for-bit with sklearn / krippendorff, with bootstrap CIs |
The agent loop unrolled into ordinary dataframe columns
Declare a task, then let an optimizer tune instructions or mine few-shot demos
Features from earlier releases for long, expensive batch jobs
Qualitative-coding and survey tooling from the 0.7.x releases
Batched generation via mlx-lm, no API keys, no network
Process customer feedback at scale
Generate embeddings, then find nearest neighbors with HNSW
Classify documents with reasoning, reflection, and confidence scores
Six inference targets: five hosted providers plus on-device MLX
Default model: gpt-4o-mini
Default model: claude-opus-4-8; supports cache=True for prompt caching
Default model: us.anthropic.claude-haiku-4-5-20251001-v1:0; region resolved from AWS_REGION / AWS_DEFAULT_REGION
Default model: gemini-2.5-flash; native system_instruction and JSON-schema structured outputs
Default model: llama-3.3-70b-versatile; GROQ_BASE_URL overrides the endpoint (0.6.0+)
No API key, no network: the server engine points at a local OpenAI-compatible endpoint, and in_process drives mlx-lm directly
Core expressions exported from polar_llama
| Function | Purpose |
|---|---|
| inference_async(expr, *, provider, model, response_model, cache, system_prompt, checkpoint, usage, price_table, dedupe, response_cache, dedupe_stats) | Parallel async inference; plus prompt caching, checkpointing, usage/cost, dedupe and a response cache |
| inference(expr, *, provider, model, response_model) | Synchronous inference (deprecated in favor of inference_async) |
| inference_messages(expr, *, provider, model, response_model, cache, checkpoint, usage, price_table, dedupe, response_cache, dedupe_stats) | Multi-turn conversation inference over JSON or List(Struct) message arrays |
| inference_stream(expr, *, provider, model, on_token, messages) | Token-by-token streaming; returns Struct{text, finished} per row |
| string_to_message(expr, *, message_type) | Convert text to a {role, content} message |
| combine_messages(*exprs) | Merge message columns/arrays into one ordered conversation |
| tag_taxonomy(expr, taxonomy, *, provider, model) | Classify text against a taxonomy with reasoning, reflection, and confidence |
| embedding_async(expr, *, provider, model) | Parallel embedding generation (OpenAI, Gemini, Bedrock) |
| cosine_similarity / dot_product / euclidean_distance(vec1, vec2) | Rust-powered vector similarity metrics |
| knn_hnsw(query_expr, reference_expr, *, k) | Stateless approximate nearest-neighbor search via HNSW |
| mcp_tools(transport, *, timeout_s) | Fetch tool definitions from an MCP server (tools/list) |
| tools_to_response_model(tools, *, model_name) | Build a Pydantic emission schema so the LLM emits structured tool calls |
| execute_tool_calls(expr, *, transport, executor, tools, concurrency, timeout_s) | Run every emitted call of every row in parallel; failures are data |
| tool_results_to_message(expr, *, role) | Render tool results as a message for the synthesis inference pass |
| Signature / Predict / evaluate / BootstrapFewShot / InstructionOptimizer | DSPy-style prompt optimization engine (polar_llama.optimize) |
| Checkpoint(path, *, flush_every, retry_failed, on_mismatch) | Checkpoint store configuration for checkpoint= |
| register_model_price(provider, model, *, input_per_1m, output_per_1m, cached_input_per_1m) / set_price_table(table) | Add or override prices used for cost_usd |
| ResponseCache(path, ttl, on_mismatch) / DedupeStats() | Persistent cross-job response cache and dedupe counters |
| cluster_embeddings(expr, *, k, k_min, k_max, max_iter, n_init, seed, silhouette_sample) | Whole-column spherical k-means with automatic k selection |
| induce_codebook(df, column, *, provider, model, embedding_column, k, n_exemplars, ...) | Embed, cluster, and LLM-name a codebook; returns .df and .codebook |
| apply_codebook(expr, codebook, *, provider, model) / codebook_to_taxonomy(codebook) | Multi-label coding against a codebook / bridge to tag_taxonomy |
| cohens_kappa(a, b, *, weights, n_bootstrap, ci, seed) / krippendorffs_alpha(cols, *, level, n_bootstrap, ci, seed) | Inter-rater reliability as aggregation expressions |
| quality_report(df, config, *, output_column) / QualityConfig(...) | Per-respondent survey quality flags plus a summary table |
| straightlining_score / gibberish_score / duplicate_answer_score / response_length_score / speeder_score / ai_likelihood | The individual quality scores as standalone expressions |
| col(...).llama.inference_local(*, model, system, engine, base_url, max_tokens, temperature, top_p, stop, usage, price_table) | On-device inference on Apple Silicon via mlx-lm |
| polar_llama.local.make_local_inference_fn(model, *, engine, collapse, max_tokens, ...) | Build an inference_fn that backs the optimizer with on-device Gemma 3n |
Every expression is also available on the fluent .llama namespace (pl.col("text").llama.inference_async(...), .llama.to_message(...), .llama.embedding(...), .llama.inference_stream(...), .llama.cohens_kappa(...), and so on). DataFrame-level orchestration functions (induce_codebook, quality_report) are plain functions, not namespace methods.
Set up your API keys and overrides in a .env file:
Share a cached system prefix across rows (Anthropic cache_control):
Run tests with configured providers:
Process large datasets with AI insights: sentiment analysis, classification, entity extraction with validated structured outputs
Resume after crashes, track spend per row, and never pay twice for the same request
Induce codebooks, measure LLM/human agreement, flag low-quality respondents, and fold reviewer corrections back into the prompt
Let the LLM call databases, internal APIs, or MCP servers at scale, with every call, result, and retry as an ordinary dataframe column
Run classification, extraction, or tuning on local models with no API keys and no data leaving the machine
Bootstrap few-shot demos or search for better instructions against a labeled dataset, entirely offline or on-device
Licensed under MIT.
Questions or issues? Open one on GitHub.