implement

name	implement
description	Use when implementing a feature, adding functionality, fixing a bug, or modifying behavior in the SMG repository — routes to subsystem-specific recipes and enforces step-by-step execution

SMG Implementation Workflow

The Iron Law

NO IMPLEMENTATION WITHOUT FOLLOWING THE SUBSYSTEM-SPECIFIC RECIPE

Identify what you're building. Load the recipe. Follow the steps. Verify at each step.

The Hard Gate

Do NOT write implementation code until you have: 1. Identified the implementation type from the detection table below 2. Loaded the matching recipe file(s) 3. Created a task for each step in the recipe

Escape hatch: Single-file changes under 20 lines that don't touch config/types.rs, crates/protocols/, main.rs (CliArgs or conversion functions), or bindings/ may skip the full recipe. You MUST still chain to smg:contribute before PR.

Detection Table

Signal in User Request	Recipe to Load
CLI flag, config field, YAML config, RouterConfig	@config-plumbing.md
Routing policy, load balancing, worker selection	@routing-policy.md
Tool call, function call, parser format	@tool-parser.md
Reasoning, thinking, chain-of-thought parser	@reasoning-parser.md
Python binding, Go SDK, FFI, PyO3, maturin	@bindings-update.md
K8s, service discovery, pod, worker lifecycle, label	@discovery-feature.md
gRPC, backend client, tonic, streaming	@grpc-backend.md
Storage, database, PostgreSQL, Oracle, Redis, data connector	@storage-backend.md
WASM, WebAssembly, plugin, middleware hook	@wasm-plugin.md
Auth, API key, JWT, OIDC, role, permission	@auth-feature.md
Metrics, tracing, logging, Prometheus, OTEL	@observability-feature.md
Mesh, gossip, CRDT, cluster, partition, SWIM	@mesh-feature.md
MCP, tool execution, approval workflow	@mcp-feature.md
KV cache, radix tree, prefix matching, positional indexer	@kv-index-feature.md
Image, audio, vision, multimodal, media	@multimodal-feature.md
Provider-compatible API router (Anthropic /v1/messages, Gemini /v1/interactions), RoutingMode variant, new API surface	@provider-api.md
Priority scheduler, admission, preemption, queue, reservation, autoscaling	@scheduler-feature.md
Multi-tenancy, tenant, tenant policy, tenant resolution	@tenancy-feature.md
Rate limit, token bucket, concurrency cap	@rate-limit-feature.md

Subsystems without a dedicated recipe yet

These are real, actively-developed subsystems that don't yet have a step-by-step recipe. Read the listed code with smg:map, then follow the general pattern (implement → test → verify → smg:contribute). config-plumbing.md usually co-applies.

Signal in User Request	Where it lives
Provider API: Responses, Conversations, Realtime (for Anthropic/Gemini-style API routers see @provider-api.md)	model_gateway/src/routers/{responses,conversations,common/realtime}/
Client SDK generation	clients/openapi-gen/ (make generate-clients)

If multiple match: Load all matching recipes. config-plumbing.md almost always co-triggers with other recipes (most features need a config field).

If none match: This is a novel change. Read the codebase architecture with smg:map first, then follow the general pattern: implement → test → verify → chain to smg:contribute.

All recipes were rewritten and verified against the codebase (2026-06; re-verified against HEAD 2026-07-15). They reflect current trait/type names and paths; still run each recipe's cargo check/cargo test step as you go.

Process

1. DETECT:  Match user request to detection table
2. LOAD:    Read the matching recipe file(s)
3. PLAN:    Create tasks from recipe steps
4. EXECUTE: For each step:
            a) Follow the step's instructions (file path, code pattern)
            b) Run the verification command
            c) Confirm expected output
            d) If verification fails: fix before proceeding
5. CHAIN:   When all steps complete, invoke smg:contribute

Rationalization Prevention

Excuse	Reality
"I know this subsystem, I don't need the recipe"	The recipe exists because people who know the subsystem still miss the two-path config rule and bindings update.
"This is a trivial change"	Check the escape hatch conditions. If it touches config/protocols/bindings, it's not trivial.
"I'll check the recipe after I write the code"	That's not following the recipe. That's post-hoc rationalization. Load first.

Red Flags — STOP

• Writing implementation code before loading a recipe
• Skipping verification steps within a recipe
• Not checking whether config-plumbing.md co-applies
• Marking implementation complete without chaining to smg:contribute
• Assuming a change is trivial without checking the escape hatch criteria

Skill Chaining

When implementation is complete: invoke smg:contribute to run the 5-step quality gate before PR.

Before submitting: self-review with smg:review-pr.