The Coral Server is the backbone of the Coral Protocol’s runtime environment. It acts as the engine that runs multi-agent sessions, executes agent logic, and mediates communication between AI agents.
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In essence, a Coral Server is an implementation of the Model Context Protocol (MCP) – a standardized interface for connecting AI models and tools – which enables agents to request model inferences or use tools through a unified API.
Multiple Coral Servers can operate on different nodes across the Internet, each hosting a collection of “Coralized” agents, MCP tool servers, and wallets, all secured by an underlying blockchain network.
This distributed design means Coral Servers coordinate local agents on each host while also communicating with other Coral nodes to form a global “society” of AI agents.
Each Coral Server is a control-plane hub for agent collaboration on its host. It listens for incoming requests (from user applications or other agents) and orchestrates the appropriate agents to handle those requests. Internally, the Coral Server implements several core services of the Coral Protocol:
Structured Interaction Mediation
The server manages all messaging between agents (and between users and agents)
via persistent communication threads. It can create new conversation threads
for a task, add or remove agent participants, and deliver messages to the
correct recipients. This thread-based approach keeps conversations organized
and contextual – each thread has a defined scope and history, preventing chaos
even as multiple agents talk concurrently.
Agent Management and Discovery
Agents register themselves with the Coral Server, advertising their
capabilities and roles. The server maintains a registry of available agents
(each with a unique identity and metadata) that can be discovered and invoked
by others. This allows dynamic composition of agents for tasks without
hard-coding connections.
Mention-Based Messaging
Coral supports mention semantics in threads – an agent can tag another agent
(by ID) in a message to direct it to them. The Coral Server handles these
mentions by notifying the targeted agent when they are mentioned in a thread.
This ensures efficient, targeted communication within a group discussion, as
agents only get notified of messages relevant to them.
Secure Task Coordination
For complex tasks, the Coral Server works with Coral’s Task Management service
to break down a job into subtasks and assign them to the appropriate
specialist agents. It coordinates multi-agent workflows, making sure each
agent knows its role and sequence in the task. The server enforces any
specified policies (for example, only agents with certain roles or permissions
can join particular threads) so that collaboration remains safe and organized.
Built-in Economic Transactions
Coral Server integrates secure payments into agent interactions. If a task
involves payment (for example, paying agents for their service), the Coral
Server invokes Coral’s Secure Payments service to create an on-chain escrow
Session Vault for the session. Funds are deposited to the vault at session
start and are only released when agents complete the task and
cryptographically claim their share, providing trust that agents get paid only
upon successful completion. All payment transactions are recorded on the
blockchain ledger, giving an immutable audit trail linked to the session’s ID
(e.g. one can verify which task a payment was for). This trust layer ensures
accountability and incentive alignment among agents.
MCP Integration for Tools/Models
Because the Coral Server adheres to MCP standards, it can easily connect
agents to external tools and model servers. Each agent instance launched by
Coral is tied to an underlying MCP server or runtime that actually executes
the AI model or tool for that agent. The Coral Server abstracts these details:
when an agent needs to use a resource, it issues an MCP request through the
Coral Server, which the MCP server fulfills (e.g. running an ML model,
querying a database, etc.). This design lets Coralized agents run anywhere
(locally or remotely) as long as they speak MCP, and the Coral Server will
coordinate with them seamlessly.
In practice, running a Coral Server provides your AI system with a ready-made infrastructure for agent collaboration. Once agents are registered, the server handles the heavy lifting of messaging and orchestration. For example, if a user asks a question, a UI agent (user-facing agent) can call the Coral Server to start a new session and thread with the relevant expert agents; the Coral Server then routes the question to those agents, manages the conversation thread as they work together on the answer, and returns the result to the UI agent – all while enforcing the protocols above. This allows developers to plug agents into the Coral ecosystem without reinventing coordination logic.
The Coral Server currently provides a set of tools/APIs that agents and developers can use to interact with the system.
Agent Registration
Agents can register themselves with the server (advertising their ID and
capabilities) so they can be discovered by name or type. A utility like
list_agents is available to query all agents known to the server.
Thread Management
Agents (or client applications) can create and manage communication threads
through commands like create_thread (to start a new thread for a task),
add_participant or remove_participant (to join or leave agents in a
thread), and close_thread (to gracefully end a thread once the task is
done). These tools correspond to Coral’s interaction mediation features,
allowing programmatic control over collaborative sessions.
Messaging
Within threads, agents use server APIs to send and receive messages. For
instance, an agent can send_message to post a message in a specific thread,
and another agent can wait_for_mentions to be notified of any new message
that mentions it. The Coral Server ensures messages are delivered only to
thread participants and enforces the mention-based targeting (so an agent can
“call” another by mention instead of broadcasting to all).
Multiple Connectivity Modes
Coral Server supports different modes of operation for integration. It can run
in a simple STDIO mode for local process-to-process piping, or as an HTTP/SSE
(Server-Sent Events) server to support web clients and remote agents. In the
future, remote mode will allow Coral Servers on different machines to
connect and share their agents in a global network (so an agent on one Coral
Server can join a thread on another), effectively merging their “society of
agents”.
Privacy and Security Controls
The server works with Coral’s identity and role system to enforce boundaries
on information. Agents have scoped memory (private, thread, session) and the
server will not, for example, let an agent access another thread’s data if
it’s not a participant. Authentication mechanisms (like developer API keys or
DIDs for agents) ensure that only authorized agents join and that all
interactions can be traced to verified identities.
The Coral Server is the local coordinator that ties together the Coral Protocol’s components on a given machine.
It sits between the application layer and the agent layer.
On the top side, user applications or UIs send high-level intents (e.g. user queries or tasks) to the Coral Server via its API.
On the bottom side, the Coral Server launches or connects to the actual agent processes (each backed by an MCP server or other runtime) that will fulfill those tasks.
It also connects to the blockchain layer underneath for any trust-critical operations (payments, logging important events).Imagine you are deploying an AI assistant that uses multiple specialized agents (a planning agent, a coding agent, a research agent, etc.).
By running a Coral Server, you gain a common platform where all these agents register and speak a common language.
When a user asks a complex question, the Coral Server can do the following behind the scenes:
Session Setup: Create a new session and conversation thread for this question, perhaps instantiating a few agent instances (if not already running) and adding them as participants.
Orchestration: Mediate the dialogue – the planning agent might break down the task and delegate subtasks to the coding and research agents within the thread. The server ensures each message or subtask result goes to the right agent, preserving context (each agent can access the thread’s shared memory and history to know what’s happening).
Tool calls via MCP: When an agent needs to call an external API or a heavy ML model, it issues an MCP request. The Coral Server forwards this to the appropriate MCP server (which might be an external service or a local worker) and then routes the result back into the thread conversation for other agents to see.
Result Aggregation: Once the agents collectively produce an answer, the Coral Server delivers the final compiled answer back to the requesting application (e.g. to the UI agent which then shows it to the user).
Teardown and Logging: After completion, the session/thread can be closed. If payments were involved, the server triggers the settlement (agents claim payment from the escrow, any remainder is refunded). The entire interaction’s log remains available for auditing or debugging if needed (each step was recorded in the thread history, and any payment on-chain is tied to this session).
By providing these capabilities out-of-the-box, Coral Server saves developers from implementing the nitty-gritty of multi-agent communication, context management, and trust.
It “glues” agents together into a coherent system.
In summary, Coral Server is a powerful facilitator that integrates communication, coordination, and trust for the Internet of Agents – enabling your agents to focus on their tasks while it handles the rest.