Simplellmfunc Developer

SimpleLLMFunc Framework Development

When to use this skill

• Use this skill when the task changes the framework itself, not just an app built on it.
• Typical triggers: editing SimpleLLMFunc/, tests/, docs/, spec/, built-in tools, runtime primitives, decorator semantics, event-stream behavior, provider adapters, TUI utilities, or contributor docs.

Core development philosophy

• LLM is Function: preserve the framework's function-first design — LLM calls are indistinguishable from Python function calls.
• Prompt as Code: docstrings are system prompts. Code and prompts are never separated.
• Context-Centric: each provider request is compiled from invocation configuration, a base transcript/history, and runtime transcript patches. ContextMutation is an internal typed patch protocol, not the whole context source of truth. No component may directly modify the live ReAct transcript.
• Keep public behavior explicit and typed.
• Favor small, composable modules over hidden orchestration.
• Prefer explicit boundaries between pure transforms, state mutation, and orchestration side effects. Recent selfref/ReAct work depends on keeping those lines sharp.
• Follow repo-grounded conventions instead of generic framework habits.
• When docs and code disagree, source and tests are the final authority.

Default implementation workflow

1. Read the relevant docs, tests, and source before changing behavior.
2. Map the affected layer: decorator, compile boundary, ReAct runtime, tool system, runtime primitives, interface, hooks, or docs/spec.
3. Write or update tests first for the behavior you are changing.
4. Make the smallest coherent implementation change.
5. Run targeted tests, then broader tests if the change touches shared behavior.
6. Update docs/examples/specs when user-facing behavior or architecture changed.

TDD and validation loop

• Start with a failing or missing test that captures the new behavior.
• Use red -> green -> refactor.
• Prefer focused unit tests in the mirrored tests/ location.
• Add or update a runnable example when the feature is user-facing.
• If behavior changes affect docs or spec, update them in the same change.

Project map

L1. Decorator Layer (llm_decorator/)

Public entry points and invocation contract building.

• llm_function_decorator.py: @llm_function — returns an LLMFunction callable instance; await instance(...) gives typed result, instance.stream(...) yields ReactOutput
• llm_chat_decorator.py: @llm_chat — returns an LLMChat callable instance; calling it yields a ReactOutput async stream and provides a stable SelfRef agent identity
• invocation_spec.py: InvocationSpec, PromptContract, TranscriptSeed
• invocation_builder.py: build_function_invocation_spec(), build_chat_invocation_spec()
• prompt_contract.py: prompt templates, XML Schema generation, type descriptions
• signature.py: parse_function_signature(), trace_id, log context
• utils/tools.py: process_tools(), collect_tool_prompt_specs()
• selfref_sync.py: legacy compatibility shim around SelfRefSession; active llm_chat binding/session orchestration lives in LLMChat plus runtime/selfref/session.py

L2+L3. Compile Boundary + ReAct Runtime (base/)

Mutation-driven context evolution and event-only ReAct loop.

Core loop modules:

• react_loop.py: run_react_loop() — main async generator, event-only
• llm_call.py: execute_single_llm_phase() — single LLM call, streaming/non-streaming
• tool_scheduler.py: schedule_tool_batch() — concurrent asyncio.Task execution
• react_hooks.py: ReActHookExecutionContext, hook lifecycle execution

Compile pipeline:

• compile_pipeline.py: single compile entry — compile_invocation_turn(), reduce_turn_context(), convert_to_llm_request()
• context_compile.py: apply_mutations(), compile_context() — mutation apply engine
• llm_input_render.py: render_llm_input_messages() — ephemeral system prompt rendering

Type contracts (base/types/):

• source.py: CompileSource, DataFromAgentConfig, DataFromSelfRef
• context.py: ContextState, CompiledContext
• compile.py: ReducedTurnContext, CompiledTurnContext
• mutation.py: ContextMutation union type (10 variants)
• react.py: ReactLoopState
• llm.py: SingleLLMCallResult
• scheduler.py: ToolSchedulerResult

Message and tool sub-modules:

• messages/: assistant message building, usage extraction, multimodal content, validation
• tool_call/: extraction, execution, streaming state, validation
• type_resolve/: type description, XML round-trip, multimodal detection
• post_process.py: response → typed result (XML → Pydantic)

Runtime Primitive System (runtime/)

• primitives.py: PrimitiveRegistry, PrimitivePack, PrimitiveCallContext, @primitive()
• worker_proxy.py: WorkerRuntimeProxy, WorkerRuntimeNamespace, PrimitiveTransport
• selfref/state.py: SelfReference public facade, lifecycle, compatibility exports
• selfref/store.py: durable history/source store
• selfref/active_turn.py: active memory key, fork context, runtime toolkit, template params, active ReAct state contextvars
• selfref/mutations.py: pending compaction/context/destructive mutation queues
• selfref/memory_api.py: self_reference.memory[...] proxy/handle API
• selfref/context_memory.py: context snapshots, experience CRUD, compaction commit, direct memory editing API
• selfref/agent_binding.py: recursive agent callable binding state
• selfref/fork_manager.py: fork/spawn/gather lifecycle and result materialization
• selfref/fork_utils.py: fork helper functions and compatibility constants
• selfref/session.py: SelfRefSession — invocation-scoped plugin implementing ReAct hooks
• selfref/context_ops.py: parse_context_messages(), build_context_messages_from_state_data(), canonicalize_context_messages()
• selfref/primitives.py: selfref primitives (guide, context.inspect/remember/forget/compact, fork.is_bound/spawn/gather_all)

Built-in Tools (builtin/)

• pyrepl.py: PyRepl public facade
• pyrepl_execution.py: execute/reset worker protocol orchestration
• pyrepl_worker_client.py: subprocess and multiprocessing queue lifecycle
• pyrepl_worker_mixin.py: facade-compatible worker lifecycle wrappers
• pyrepl_primitive_host.py: runtime backend, primitive registry, primitive RPC, fork clone integration
• pyrepl_tools.py: execute/reset tool creation and output formatting
• pyrepl_audit.py: audit log writer
• pyrepl_input_bridge.py: process-wide input request/reply bridge
• pyrepl_input_mixin.py: PyRepl input submission API
• file_tools.py: FileToolset — workspace-scoped file tools with stale-write protection

Event Stream (hooks/)

• events.py: 14 ReActEvent subtypes
• stream.py: ReactOutput, ResponseYield, EventYield, type guards
• event_bus.py: EventBus — event ingress with origin metadata
• event_emitter.py: ToolEventEmitter, NoOpEventEmitter

Interface Layer (interface/)

• llm_interface.py: LLM_Interface abstract base class
• openai_compatible.py: OpenAICompatible adapter
• openai_responses_compatible.py: OpenAIResponsesCompatible adapter
• key_pool.py: APIKeyPool — multi-key rotation
• token_bucket.py: token-bucket rate limiting

Infrastructure

• logger/: structured logging, trace_id, async context manager
• observability/: Langfuse trace/span integration
• type/: multimodal types (Text, ImgUrl, ImgPath) and canonical chat input (UserChatMessage)
• utils/tui/: Textual TUI integration

Tests (tests/)

Mirror of behavior and architecture; often the fastest place to infer conventions.

Naming and style rules

• File names: snake_case.
• Functions: snake_case.
• Classes: PascalCase.
• Constants: UPPER_SNAKE_CASE.
• Public APIs should carry type annotations.
• Public user-facing callables should have useful docstrings.
• Follow the repo's existing formatting and PEP 8 style.

Framework-specific development rules

Core rule: runtime transcript patch boundary

LLM-visible messages are compiled from invocation config, a base transcript/history, and runtime patches:

1. Producers (LLM call, tool exec, selfref hooks) emit ContextMutation objects for runtime transcript edits.
2. react_loop collects mutations before each compile boundary.
3. compile_context() applies mutations in order via apply_mutations().
4. The compile pipeline combines that patched transcript with invocation config and SelfRef source data before rendering provider messages.

Do not introduce code that directly mutates ContextState.messages outside of apply_mutations(). Do not let tools or primitives write directly to the live transcript. Also do not describe mutations as the source of all context: docstrings, template params, tool schemas, and initial history are separate compile inputs.

SelfRef rules

• SelfReference (runtime/selfref/state.py) is the public facade for the durable backend; do not re-expand it into a god object.
• SelfRefSession (runtime/selfref/session.py) is the invocation-scoped plugin that implements ReAct hooks (collect_context_mutations, finalize, etc.).
• Keep pure context parsing/rendering in runtime/selfref/context_ops.py.
• Keep durable history/source storage in runtime/selfref/store.py.
• Keep active turn contextvars and active ReAct state lookup in runtime/selfref/active_turn.py.
• Keep pending mutation/compaction queues in runtime/selfref/mutations.py.
• Keep context memory operations, experience CRUD, compaction commit, and direct memory editing in runtime/selfref/context_memory.py.
• Keep fork/spawn/gather lifecycle behavior in runtime/selfref/fork_manager.py and pure-ish helpers/constants in runtime/selfref/fork_utils.py.
• LLMChat is the stable callable agent instance bound into SelfReference; keep per-call mutable state inside invocation locals / SelfRefSession, not on shared instance fields.
• llm_decorator/selfref_sync.py is a legacy compatibility shim; do not move new lifecycle logic there unless intentionally reviving that layer.
• SelfRef can only affect the system through: source snapshot, pending intents → mutations, finalize side effects.
• runtime.selfref.fork.spawn(...) children inherit the pre-fork context snapshot. Do not reintroduce the parent's pending assistant tool-call message into child-visible history.

ReAct runtime rules

• The core is event-only: run_react_loop() always yields ReactOutput.
• There is no enable_event parameter; event mode is the only mode at the core level.
• New terminal behavior should flow through the shared finalize path so before_finalize stays consistent across event, abort, and max-tool-cap exits.
• Abort is mutation-producing behavior: AssistantTruncatedMutation for LLM abort, ToolCancelledMutation for tool abort.
• Do not add dual-mode (event/non-event) logic inside react_loop.py, llm_call.py, or tool_scheduler.py.

Decorator rules

• @llm_function returns LLMFunction; @llm_chat returns LLMChat. Preserve function-like metadata (__wrapped__, __name__, __doc__, __annotations__, __signature__) when changing them.
• Multimodal input policy: llm_function should use explicit ImgUrl / ImgPath typed parameters, while llm_chat should prefer one OpenAI-compatible UserChatMessage user-message object.
• Do not reintroduce closure-only wrapper implementations for SelfRef binding; SelfRef should bind the stable LLMChat instance.
• There is no enable_event or return_mode decorator parameter; llm_chat always yields ReactOutput, and llm_function.stream(...) yields ReactOutput.
• Prefer async def for decorated public patterns and tool implementations.
• Keep docstring-parsed contracts in sync with behavior. This matters for @tool and runtime primitives.
• Runtime primitive docstrings must include Best Practices; registration fails without them.
• Preserve history semantics in llm_chat: history and chat_history are special names.
• Preserve structured output parsing behavior unless the task explicitly changes it.

Provider adapter rules

• Keep wire-format differences in the adapter layer under SimpleLLMFunc/interface/.
• Do not leak Responses-specific request/stream contracts into ReAct or decorator code unless the public framework contract is intentionally changing.
• OpenAIResponsesCompatible should remain a first-class adapter, not a special case hidden inside ReAct. System prompts map to Responses instructions, and Responses-specific reasoning/tool-stream handling belongs in the adapter.

Test rules

• Treat tests as executable API documentation for subtle cases like self-reference, event mode, and provider compatibility.
• Add architecture tests (invocation isolation, compile single-entry, history authority) when changing the invocation/compile/finalize pipeline.

Documentation and spec rules

• Update mintlify_docs/ when user-facing behavior changes.
• Update spec/ when module responsibilities, architecture map, or repo-wide guidance changes.
• Keep examples runnable and aligned with current behavior.
• Use progressive disclosure in skills and docs: concise guidance in the main file, details in reference docs.
• Keep provider.json format docs and .env / environment-variable docs aligned with actual loader and observability behavior.
• Keep the packaged skills/ directory and the simplellmfunc-skill export CLI aligned so installed users can export the current skill contents correctly.
• When Responses adapter behavior or selfref fork behavior changes, update packaged skills/ docs in the same change, not only mintlify_docs/.
• Treat AGENTS.md as a feedback-loop artifact: when recurring agent mistakes reveal missing environmental guidance, update the file so the fix lives in the system instead of only in maintainer memory.

Read these reference docs as needed

• Architecture and contributor map: reference/project-map.md
• TDD, tests, and validation expectations: reference/testing-and-tdd.md
• Coding conventions and naming rules: reference/style-and-spec.md
• Framework-specific gotchas: reference/framework-gotchas.md
• PyRepl architecture, IPC, primitive RPC, event streaming, and image artifact capture: reference/pyrepl-architecture.md
• Docs and examples workflow: reference/docs-and-examples.md
• Maintainer workflow notes: reference/AGENT.md
• Contributor guide: reference/contributing.md
• Mirrored repo spec: reference/spec/project-map.md, reference/spec/overall-spec.md, reference/spec/primitive-dev-api-plan.md, reference/spec/meta.md
• Developer examples: examples/add_runtime_primitive_pattern.py, examples/test_first_decorator_change.md, examples/update_docs_checklist.md