A proxy that adapts Claude Code tool calls to work with non-Anthropic APIs like OpenAI, Azure, and Ollama. Write once using Claude Code's format, then route to any provider with automatic translation, fallback, and cost tracking.
CLASP breaks down the walls between AI coding platforms by acting as a universal translation layer that enables Claude Code workflows to run seamlessly with any LLM provider. It's the bridge that connects best-in-class development tools with the flexibility of choosing your preferred language model, whether for cost optimization, capability requirements, or simply avoiding vendor lock-in. In an ecosystem where AI coding tools are often tightly coupled to specific providers, CLASP provides the freedom to use the right model for each task without sacrificing your preferred tooling.
Universal API Translation
The proxy intelligently translates API calls between different provider formats, converting Anthropic's message structure to OpenAI's chat completion format, mapping Claude's system prompts to provider-specific equivalents, and transforming tool/function calling syntax across different schemas. This isn't simple passthrough—CLASP understands the semantic meaning of each API element and translates it preserving intent rather than just structure.
Provider-specific quirks are handled transparently: some providers paginate long responses while others stream them as single chunks, rate limit structures vary from per-minute tokens to per-day requests, error codes and formats differ across providers, and retry/backoff strategies need provider-specific tuning. CLASP abstracts all these differences behind a consistent interface, so your code doesn't need to know which provider is backing each request.
Authentication management supports multiple credential types including API keys for services like OpenAI, Anthropic, Cohere, OAuth flows for enterprise Azure OpenAI deployments, custom headers for self-hosted model servers, and session tokens for providers with more complex auth patterns. CLASP rotates credentials automatically when approaching rate limits, securely stores credentials outside of application code, and validates permissions before routing requests to ensure credentials have appropriate scopes.
Advanced Feature Support
CLASP supports the full feature set that modern AI coding workflows require. Streaming responses work identically across all providers—even those that don't natively support streaming—by buffering and chunking complete responses to simulate streams. This ensures your UI can display progress and provide responsive feedback regardless of the underlying model's streaming support.
Function calling translation is particularly sophisticated since every provider implements tool usage differently. Anthropic's tool syntax differs from OpenAI's function calling, which differs from open-source frameworks' agent tool formats. CLASP normalizes these into a single schema your code uses, then translates to the provider's specific format. It handles the full function calling flow: describing available functions in the provider's schema format, parsing function call requests from model responses, executing functions through your defined callbacks, and returning results in the expected format for multi-turn function calling conversations.
Multi-turn conversations present challenges since conversation formats vary (message arrays vs. single strings, role naming differences, context window tracking). CLASP maintains conversation state efficiently across turns, automatically managing context windows by trimming old messages when approaching limits, preserving critical system prompts and recent context, and using provider-specific strategies like Claude's conversation continuation or GPT's max_tokens to ensure long conversations remain coherent.
Intelligent Routing and Fallback
The routing engine selects optimal providers based on multiple criteria including model capability requirements (does this task need function calling? reasoning? multimodal understanding?), cost constraints and budgets, latency requirements (some providers have faster inference), availability and rate limit status, and historical performance for similar queries. This dynamic routing ensures each request uses the best available model for its specific needs.
Automatic fallback handling provides resilience when primary providers fail. If a request to OpenAI times out, CLASP can automatically retry with Anthropic. If you hit rate limits on your preferred provider, it seamlessly switches to a backup. If a specific model is temporarily unavailable, it routes to a similar-capability alternative. This happens transparently without application code needing error handling for every possible provider failure mode.
Fallback strategies are configurable: strict mode ensures all fallbacks use models with identical capabilities even if more expensive, cost-optimized mode prioritizes cheaper alternatives even if slightly less capable, and balanced mode weighs both capability and cost. You can define custom fallback chains specifying exactly which models to try in sequence, with different chains for different task types.
Cost Optimization
Built-in cost optimization tracks usage across all providers, showing real-time and historical spending by provider, model, project, or time period. The system alerts when spending approaches budget limits, provides cost projections based on current usage patterns, and identifies opportunities to reduce costs by switching models for specific workloads.
Model selection intelligence automatically routes prompts to the cheapest model capable of handling them. Simple code completion requests use lightweight models like GPT-3.5 or Claude Haiku. Complex reasoning tasks requiring chain-of-thought upgrade to GPT-4 or Claude Opus. The system learns from past successes and failures, building a profile of which models work well for which types of requests, and continuously optimizes the cost-performance tradeoff.
Caching strategies reduce redundant API calls by identifying identical or similar prompts and reusing recent responses, implementing semantic caching that matches prompts with similar meaning even if worded differently, respecting TTL constraints to avoid serving stale responses, and invalidating cache when underlying code or context changes. Smart caching can reduce API costs by 40-60% for applications with repeated queries.
Performance Analytics
Detailed analytics provide visibility into model performance and usage patterns. Latency tracking measures time-to-first-token and total generation time across providers, identifying performance bottlenecks and comparing provider speeds for different request types. Quality metrics track task success rates, user satisfaction signals, and retry frequencies to identify models that struggle with specific tasks.
Usage dashboards visualize request volumes over time, token consumption patterns, cost trends and anomalies, error rates by provider and model type, and cache hit rates and savings. These insights guide infrastructure decisions like which provider contracts to negotiate, which models to deprecate from rotation, and where caching investments yield highest returns.
The analytics engine supports custom metrics and dimensions, allowing teams to track domain-specific quality indicators, correlate model choices with downstream application metrics, and perform cohort analysis on model performance across user segments. Exportable reports integrate with business intelligence tools for cross-functional analysis.
Development and Production Use
For development teams, CLASP enables experimentation without rewriting code. Want to test if GPT-4 Turbo handles your use case better than Claude Opus? Just update the routing config. Curious about open-source model performance? Point CLASP at a self-hosted Llama instance. Evaluating a new provider like Cohere or AI21? Add their credentials and route traffic. The abstraction layer means experimenting with new models is a configuration change, not a code refactor.
Production deployments benefit from CLASP's reliability features including automatic retry logic with exponential backoff, circuit breakers that stop routing to failing providers, health checks that preemptively avoid unhealthy backends, and graceful degradation that serves cached or default responses when all providers are unavailable. These patterns keep applications running even when AI providers experience outages.
Multi-region support allows routing to geographically closer provider endpoints for reduced latency, complying with data residency requirements by choosing region-appropriate providers, and load balancing across regions for high-availability deployments. This global infrastructure awareness makes CLASP suitable for worldwide applications with diverse latency and compliance needs.
PythonLLM ProxyMulti-ProviderAPI Gateway