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status: Implemented audience: Everyone

Talos Mental Model

Problem: Readers understand pieces but not the whole.
Guarantee: One abstraction that ties everything together.
Non-goal: Technical details—see individual pages for those.

The Core Abstraction

Talos is a graph of identities where edges are encrypted sessions, capabilities constrain actions, and audit commits facts.

            ┌─────────────────────────────────────────┐
            │            Talos Network                │
            │                                         │
            │    ┌─────────┐         ┌─────────┐     │
            │    │ Agent A │◄───────►│ Agent B │     │
            │    └────┬────┘ session └────┬────┘     │
            │         │                   │          │
            │         │    capability     │          │
            │         │    ┌───────┐      │          │
            │         └───►│ Tool  │◄─────┘          │
            │              └───┬───┘                 │
            │                  │                     │
            │              ┌───┴───┐                 │
            │              │ Audit │                 │
            │              │  Log  │                 │
            │              └───────┘                 │
            └─────────────────────────────────────────┘

Five Concepts, One System

1. Identity

Every agent has a cryptographic identity:

• Keypair: Ed25519 for signing, X25519 for encryption
• Peer ID: Unique identifier derived from public key
• DID: Decentralized Identifier (optional, anchored on-chain)

Identity is permanent unless explicitly revoked.

2. Sessions

When two identities want to communicate:

• Exchange prekey bundles
• Establish Double Ratchet session
• Every message rotates keys → forward secrecy

Sessions are ephemeral—they can be re-established if lost.

3. Capabilities

Not every agent can do everything:

• Scope: What resource/action is authorized
• Constraints: Rate limits, parameter restrictions
• Expiry: When the capability ends
• Delegation: Can be passed to other agents

Capabilities are granted, scoped, and revocable.

4. Messages

Agents exchange encrypted payloads:

• Confidential: Only recipient can decrypt
• Authenticated: Signed by sender
• Ordered: Blockchain provides global ordering

Messages are private but provable.

5. Audit

Every significant event is committed:

• Message hashes
• Capability grants
• Session establishments
• Revocations

Audit log is append-only, Merkle-proofed, blockchain-anchored.

How They Relate

graph TD
    A[Identity] -->|creates| B[Session]
    A -->|grants| C[Capability]
    B -->|carries| D[Message]
    C -->|authorizes| D
    D -->|commits to| E[Audit Log]
    C -->|commits to| E
    E -->|anchors on| F[Blockchain]

The Flow

1. Agent A has an identity
2. Agent A establishes a session with Agent B
3. Agent B grants Agent A a capability to invoke Tool C
4. Agent A sends a message invoking Tool C over the session
5. Tool C verifies the capability and executes
6. All events are committed to the audit log
7. Periodically, audit roots are anchored to the blockchain

What Lives Where

Component	Location	Persistence
Identity keys	Agent local storage	Permanent
Session state	Agent memory	Ephemeral
Capability tokens	Issued to holders	Until expiry/revocation
Messages	Encrypted in transit	Not stored (unless by recipient)
Audit log	Agent local chain	Permanent
Trust anchors	Blockchain	Permanent

Key Insight

Talos separates what you can prove from what you must reveal.

• You can prove a message was sent without revealing its contents
• You can prove a capability was valid without exposing the token
• You can prove an identity exists without revealing the private key

This is the foundation of privacy-preserving accountability.

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