AI Conversational Agent Bundle

A vertical-agnostic core for conversational agents in Symfony: the turn loop, tool execution, gates, sessions, streaming, memory, budgets and evals. Verticals (a shopping assistant, an institutional assistant) are built on top of it as capabilities.

It ports the commerce_common layer of Anthropic's commerce-agents reference to PHP; nothing in it knows about commerce.

What you get

• A streaming turn loop: Model rounds, tool calls and UI components reach the browser as server-sent events while the model is still writing.
• Tools the model can't misuse: JSON-schema validation, provenance checks (it can only act on ids a tool returned) and grounding rules that force a lookup before it answers.
• Prompt-injection fencing: Site content and tool results are quoted, never read as instructions.
• Memory across sessions: Facts about the visitor, extracted after the turn by a cheaper model, with a filter that keeps identifiers and credentials out.
• Budgets and costs: Spend limits per session, per client and per day, rate limits on the endpoints, and a ledger of what every turn spent.
• Persistence on Doctrine: Conversations, transcripts, memory and spend, with retention and a prune command.
• Evals: YAML cases run against a scripted or live model, graded by code and by a judge.

Concepts

• Capability — a unit of the vertical: tools with JSON schemas, prompt fragments, grounding rules and presentation components. Capabilities are autoconfigured (odiseo_ai_conversational_agent.capability) and assembled by the CapabilityRegistry.
• Turn loop (AgentLoop) — streams model rounds and tool calls as AgentEvents; a turn ends on text, on a budget limit or on the tool-iteration cap.
• Gates — fencing of external text (Fence), grounding rules that force a tool when the message matches a lexicon, provenance checks and payload guards on what is presented.
• Sessions and memory — ORM stores for session state, transcript, long-term facts per subject, and a spend ledger; memory extraction runs after the turn with a cheaper model.
• Presentation — ui events carrying components the host renders; the model only names them.
• Evals — YAML cases run against a scripted or live provider with a judge model.

Installation

Register Odiseo\AiConversationalAgentBundle\Bridge\Symfony\OdiseoAiConversationalAgentBundle and configure odiseo_ai_conversational_agent (bin/console config:dump-reference odiseo_ai_conversational_agent): identity, models, budgets, memory, fence, sessions, conversations, skills and evals directories.

For Claude, install symfony/ai-bundle and symfony/ai-anthropic-platform, register Symfony\AI\AiBundle\AiBundle (Flex does it) and configure the platform; the bundle wraps its ai.platform.anthropic service:

Storage

Sessions, transcripts, memory facts and the spend ledger persist through Doctrine ORM, on any platform it supports. The stores work against the four interfaces in Bridge\Doctrine\Model (ConversationInterface, MessageInterface, MemoryFactInterface, SpendEntryInterface) and never name a concrete class. Beside each one is a mapped superclass implementing it, with its XML mapping; the host extends that, names the table and adds whatever it relates to, and points the bundle at its classes:

A conversation the core creates carries the session id, the principal and the state document. Anything else the host's schema relates it to it sets through a ConversationInitializer, called on the new entity before it is persisted, while the request still knows who is asking:

Point the ConversationInitializer alias at it and the core will call it; unset, nothing happens.

Services

Every service is registered as odiseo_ai_conversational_agent.* with explicit arguments. The classes and ports a host uses are aliases, and a host replaces a port by redefining its alias: ModelProvider, ContextProvider, PrincipalResolver, TurnHook, ConsoleEnvironment, ConversationInitializer, SessionStore, MemoryStore and SpendLedger. The Anthropic adapter is registered only when symfony/ai-anthropic-platform is installed, and it needs the AI bundle's ai.platform.anthropic; without them, alias ModelProvider to your own provider. Capabilities are collected by the odiseo_ai_conversational_agent.capability tag.

doctrine:migrations:diff then produces the schema: the mappings ship here, the migration belongs to the application that runs them. Without doctrine/orm (or with orm.enabled: false) the stores are in memory and nothing outlives the process.

Retention

Two clocks. sessions.retention_days (30) is how long a session is served after its last activity; past it the widget starts a new one, but the conversation stays for the host to read. conversations.retention_days (180) is how long it is kept; memory.retention_days (null) does the same for memory facts. Null keeps them. bin/console agent:prune applies both, dropping the conversations with their messages and spend; --dry-run only counts. Run it from a daily cron.

Compatibility

The bundle is in 0.x: minor versions may break the API until 1.0.

Development

Deptrac keeps the agent free of Symfony and Doctrine: they are reached only through Bridge/ and Provider/Anthropic/.

The suite runs on SQLite in memory and needs no server. AGENT_TEST_DATABASE_URL points the ORM tests at a real one, which is what CI does for MySQL and PostgreSQL:

Demo

Want a live walkthrough of this bundle? Get in touch, or see what else we build at odiseo.io.

Credits

This bundle is maintained by Odiseo. Want us to help you build an agent on it, or with any Symfony or Sylius project? Get in touch.

License

MIT.