ADR-007: Multi-Provider Strategy 

Status 

Accepted (2024-01)

Context 

Supporting multiple providers requires:

• Dynamic provider registration.
• Priority-based selection.
• Configuration per provider.
• Fallback mechanisms.

Decision 

Use tagged service collection with priority:

# Services.yaml
Netresearch\NrLlm\Provider\OpenAiProvider:
  tags:
    - name: nr_llm.provider
      priority: 100

Netresearch\NrLlm\Provider\ClaudeProvider:
  tags:
    - name: nr_llm.provider
      priority: 90

Provider selection:

1. Explicit provider in the per-call options.
2. Otherwise the active DB-backed default configuration's provider.
3. Otherwise getProvider(null) throws a ProviderException.

There is deliberately no "first provider by priority" fallback: the implicit default-provider fallback was removed in ADR-034, so provider selection is always explicit (per-call option or the active configuration).

Consequences 

Positive:

• ● Easy provider registration.
• ● Clear priority system.
• ●● Supports custom providers.
• ● Automatic fallback.

Negative:

• ◑ Priority conflicts possible.
• ◑ All providers instantiated.
• ◑ Configuration complexity.

Net Score: +5.5 (Strong positive impact - flexible multi-provider support with minor overhead)