Refactor configuration around a single adapter interface (v0.2.0)

.rubocop.yml

@@ -21,10 +21,18 @@ Metrics/BlockLength:
     - "*.gemspec"
     - "test/**/*.rb"
 
-# Test classes are naturally long
+# Test classes are naturally long; Configuration is mostly declarative
+# (grouped settings + flat compatibility aliases)
 Metrics/ClassLength:
   Exclude:
     - "test/**/*.rb"
+    - "lib/llm_optimizer/configuration.rb"
+
+# validate!/validate_values! raise on failure and return true (like AR's save!)
+Naming/PredicateMethod:
+  AllowedMethods:
+    - validate!
+    - validate_values!
 
 # The optimize method is intentionally a pipeline — complexity is expected
 Metrics/MethodLength:

CHANGELOG.md

@@ -7,6 +7,33 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+## [0.2.0] - 2026-07-15
+
+Ease-of-use refactor: one adapter interface replaces the four caller lambdas, configuration is grouped and validated, and the Rails initializer shrinks to a minimal working config. 0.1.x initializers keep working via compatibility aliases.
+
+### Added
+- **Adapter interface** (`config.adapter`) — the single integration point between the gem and your LLM provider. Built-in adapters: `:ruby_llm` (chat + embeddings across OpenAI/Anthropic/Gemini/Bedrock/Ollama), `:open_ai` (ruby-openai, chat + embeddings), `:anthropic` (official anthropic gem, chat only). Adapter gems are lazily required with an actionable error if missing
+- `LlmOptimizer::Adapters::Custom` — wrap any provider with `chat:` / `embed:` lambdas
+- **Grouped configuration** — `config.routing.*`, `config.cache.*`, `config.compression.*`, `config.history.*`, `config.conversation.*`; flat 0.1.x keys remain as aliases
+- `config.routing.classifier_model` — enables the LLM routing classifier through the adapter (replaces hand-written `classifier_caller` lambdas)
+- **Fail-fast validation** — `LlmOptimizer.configure` validates values immediately; each `optimize` call validates cross-field consistency; `LlmOptimizer.validate!` runs the full check at boot with actionable error messages
+- **Defensive lambda invocation** (`LlmOptimizer::Invoker`) — user-supplied lambdas only receive the keyword arguments their signature accepts, so lambdas written against older signatures keep working
+- `schema` config option is now actually passed through to adapters (it was declared but unused in 0.1.7)
+
+### Changed
+- **Rails initializer template rewritten** — ~25-line minimal working config with advanced options in a commented appendix, instead of 120 lines of mixed provider examples
+- Default complex model updated from `claude-3-5-sonnet-20241022` to `claude-sonnet-4-5`
+- `embedding_model` default is now `nil` (the adapter picks its own default) and lives at `cache.embedding_model`
+- `llm_caller`, `messages_caller`, `embedding_caller`, `classifier_caller` are deprecated; when set they are wrapped in an internal legacy adapter automatically
+- Enabling the semantic cache without `redis_url` or embedding support now raises `ConfigurationError` instead of silently disabling the cache (`validate_configuration!` removed)
+- Semantic cache lookup no longer connects to a default localhost Redis when `redis_url` is unset — it logs a warning and skips the cache
+
+### Fixed
+- `llm_caller` lambdas written as `->(prompt, model:)` (the documented signature) crashed with `unknown keyword: :tools` since 0.1.6 — the gem passed `tools:` unconditionally; lambdas now only receive keywords they accept
+- History summarization injected a `[content, token_info]` array as the summary message content instead of the summary string
+- `tools` and `with_tools` are now true aliases of one value instead of two separate config keys
+- Removed dead code: unused `tools_caller` config key and the never-assigned `@_current_llm_caller`
+
 ## [0.1.7] - 2026-05-05
 
 ### Added
@@ -127,7 +154,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - `OptimizeResult` struct with `response`, `model`, `model_tier`, `cache_status`, `original_tokens`, `compressed_tokens`, `latency_ms`, `messages`
 - Unit test suite covering all components with positive and negative scenarios using Minitest + Mocha
 
-[Unreleased]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.5...HEAD
+[Unreleased]: https://github.com/arunkumarry/llm_optimizer/compare/v0.2.0...HEAD
+[0.2.0]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.7...v0.2.0
+[0.1.7]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.6...v0.1.7
+[0.1.6]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.5...v0.1.6
 [0.1.5]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.4...v0.1.5
 [0.1.4]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.3...v0.1.4
 [0.1.3]: https://github.com/arunkumarry/llm_optimizer/compare/v0.1.2...v0.1.3

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    llm_optimizer (0.1.6)
+    llm_optimizer (0.2.0)
       logger (~> 1.6)
       msgpack (~> 1.7)
       redis (~> 5.0)
@@ -107,7 +107,7 @@ CHECKSUMS
   json (2.19.3) sha256=289b0bb53052a1fa8c34ab33cc750b659ba14a5c45f3fcf4b18762dc67c78646
   language_server-protocol (3.17.0.5) sha256=fd1e39a51a28bf3eec959379985a72e296e9f9acfce46f6a79d31ca8760803cc
   lint_roller (1.1.0) sha256=2c0c845b632a7d172cb849cc90c1bce937a28c5c8ccccb50dfd46a485003cc87
-  llm_optimizer (0.1.6)
+  llm_optimizer (0.2.0)
   logger (1.7.0) sha256=196edec7cc44b66cfb40f9755ce11b392f21f7967696af15d274dde7edff0203
   minitest (5.27.0) sha256=2d3b17f8a36fe7801c1adcffdbc38233b938eb0b4966e97a6739055a45fa77d5
   mocha (2.8.2) sha256=1f77e729db47e72b4ef776461ce20caeec2572ffdf23365b0a03608fee8f4eee