---
slug: "Card"
name: "Card"
type: "Data Structures"
layer: "Infrastructure"
ref: "Card#e4b2"
sema_id: "sema:Card#mh:SHA-256:e4b2ca76f43a691e7bd7932362512a5e929c62efc6c3d2eb4a9369e5108fa074"
tags: ["Infrastructure","Data Structures"]
updated: 2026-11-11
mindscape: "bootstrap"
index_url: https://mindscape.world/scapes/bootstrap.json
url: https://mindscape.world/bootstrap/Card/
related: ["Select","Agent","Greet","LatentAttachment","Probe","AgentDiscover","NoiseInjection","PolymorphicSolver","ToolDiscovery"]
---

# Card

Structured capability advertisement: agent_id, endpoint, protocols, capabilities, metadata

Layer: Infrastructure · Category: Data Structures

## Mechanism

Structured capability advertisement enabling agent discovery before contact. [Agent](https://mindscape.world/scapes/bootstrap/Agent.md) creates CARD: {agent_id (unique), endpoint (how to reach), protocols[] (compatibility), capabilities[] (what agent claims to do), constraints (availability, rate limits, requirements), metadata (version, ttl, published timestamp)}. [Agent](https://mindscape.world/scapes/bootstrap/Agent.md) PUBLISHES card via registry, broadcast, DHT, or well-known endpoint (mechanism-agnostic). Discovering agents QUERY using [LatentAttachment](https://mindscape.world/scapes/bootstrap/LatentAttachment.md) for semantic capability matching alongside exact protocol_match. Query returns ranked CARD list. Discoverer selects promising CARDs, then [Greet](https://mindscape.world/scapes/bootstrap/Greet.md)s at card.endpoint to establish channel. CARDs have TTL — agents maintain visibility by PUBLISHING a replacement card before the previous one expires, never by editing the one already issued. CARD capabilities are CLAIMS not proofs: verification happens via [Probe](https://mindscape.world/scapes/bootstrap/Probe.md) after GREET establishes channel. It enables discovery via [Select](https://mindscape.world/scapes/bootstrap/Select.md) queries against the registry, filtering candidates by capability and protocol compatibility.

## Invariants

- Immutable after issue: a Card is never edited. A change of endpoint, protocol or capability is published as a new Card superseding the old, which is what lets a discoverer tell a current claim from a stale one rather than trusting a mutable record.
- Claims, not proofs: the capabilities a Card advertises are assertions the issuer has not demonstrated. Verification is the discoverer's, via [Probe](https://mindscape.world/scapes/bootstrap/Probe.md) after [Greet](https://mindscape.world/scapes/bootstrap/Greet.md) opens a channel.

## Failure modes

- Stale CARDs (agent changed capabilities, CARD not updated—TTL mitigates).
- False claims (CARD says X, agent cannot X—PROBE mitigates).
- Registry unavailable (discovery fails—use multiple publication methods).
- CARD spam (fake CARDs pollute discovery—use reputation/filtering).
- Privacy leak (CARD reveals too much about agent—include only necessary info).
- Version skew (CARD protocol version differs from actual—GREET catches this).

## Parameters

- `verification_tier` (Enum, {SelfReported, Verified, Bonded}): Default: SelfReported

## Data schema

```json
{
  "type": "object",
  "required": [
    "public_key",
    "claims"
  ],
  "properties": {
    "public_key": {
      "type": "string",
      "description": "Cryptographic identifier of the Agent"
    },
    "claims": {
      "type": "object",
      "description": "Map of protocols and capabilities supported"
    },
    "reputation_score": {
      "type": "number",
      "description": "Aggregate trust metric (optional)"
    },
    "endpoints": {
      "type": "array",
      "description": "Reachability addresses"
    }
  }
}
```

## Builds on

- [Select](https://mindscape.world/scapes/bootstrap/Select.md) (Infrastructure; Composes with)
- [Agent](https://mindscape.world/scapes/bootstrap/Agent.md) (Mind; References)
- [Greet](https://mindscape.world/scapes/bootstrap/Greet.md) (Infrastructure; References)
- [LatentAttachment](https://mindscape.world/scapes/bootstrap/LatentAttachment.md) (Mind; References)
- [Probe](https://mindscape.world/scapes/bootstrap/Probe.md) (Infrastructure; References)

## Used by

- [AgentDiscover](https://mindscape.world/scapes/bootstrap/AgentDiscover.md) (Society; References)
- [NoiseInjection](https://mindscape.world/scapes/bootstrap/NoiseInjection.md) (Mind; References)
- [PolymorphicSolver](https://mindscape.world/scapes/bootstrap/PolymorphicSolver.md) (Mind; References)
- [ToolDiscovery](https://mindscape.world/scapes/bootstrap/ToolDiscovery.md) (Society; References)

## Identity

- Sema ID: `sema:Card#mh:SHA-256:e4b2ca76f43a691e7bd7932362512a5e929c62efc6c3d2eb4a9369e5108fa074`
- Ref: `Card#e4b2`
- Supersedes:
  - `sema:Card#mh:SHA-256:e307b9bce7530dd5d86a1e6e4cd2252765f4154b6e3e6c1f1f1ac3e544666495`
  - `sema:Card#mh:SHA-256:c9f028ecd6e890702f25417a076aed7d352790d1c02fd9656488daea00db2626`
  - `sema:Card#mh:SHA-256:84b75e4aa9df317e013f042ff44e2cc81e5f3092d405375f2c84e4dad9d39b0b`
  - `sema:Card#mh:SHA-256:ed287a652085f4e54a58e1b76a59016d74fa7edf51f918730d0338698aca979d`

## Links

- [Pattern page](https://mindscape.world/bootstrap/Card/)
- [View in the interactive graph](https://mindscape.world/bootstrap/#Card)
- [JSON](https://mindscape.world/scapes/bootstrap/Card.json)
- [Index of all patterns](https://mindscape.world/scapes/bootstrap.json)