The core bypass implementation that transforms hermes-agent's API requests to match Claude Code's fingerprint. It implements billing header signing using SHA-256 with Anthropic's salt, system prompt relocation moving non-identity entries to first user message, tool name rewriting to match MCP namespacing expectations, Stainless SDK header spoofing, orphaned tool pair repair, effort stripping for haiku models, temperature fixing for Opus 4.6 adaptive thinking, and account metadata mapping. Each feature is isolated, well-documented, and demonstrates deep understanding of Anthropic's API validation mechanisms. The module is highly reusable for similar API request modification tasks with minimal adaptation.

A clean, reusable import hook mechanism that uses Python's MetaPathFinder to intercept specific module imports and apply patches at runtime. It safely patches the target module's loader to apply modifications after the module loads but before it's used, ensuring the bypass is active for all subsequent requests. The implementation handles recursion avoidance, proper error handling, and follows Python's import system best practices. This pattern is broadly applicable to any runtime patching scenario and could be extracted with minimal changes to target different modules or apply different patches.