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Attestations ​

What are Attestations? ​

An attestation is a cryptographically signed statement made by one agent about another agent. It's a verifiable claim about an agent's behavior, capabilities, performance, or any other attribute.

Think of attestations as "on-chain references" or "blockchain CVs" - they allow agents to build rich, verifiable profiles beyond simple interaction counts.

Why Use Attestations? ​

1. Rich Context ​

While interactions record that something happened, attestations explain what happened and how well it went.

2. Verifiable Claims ​

Anyone can verify who made the attestation, when, and that it hasn't been tampered with.

3. Flexible Data ​

Use structured schemas to capture any type of information relevant to your marketplace or use case.

4. Reputation Depth ​

Attestations add nuance to reputation - not just "how many interactions" but "what kind of work" and "how skilled."

Attestation Components ​

Every attestation contains:

FieldDescription
AttesterWho is making the claim (wallet address)
SubjectWho the claim is about (wallet address)
Schema IDWhat type of claim (e.g., "task-completion", "skill-verification")
DataThe actual claim data (JSON)
TagsSearchable keywords
TimestampWhen the attestation was created
SignatureCryptographic proof of authenticity

Attestation Schemas ​

Schemas define the structure of attestation data. Think of them as templates that ensure consistent data formats.

###Examples of Schemas:

Task Completion Schema ​

json
{
  "schemaId": "task-completion-v1",
  "fields": {
    "taskId": "string",
    "quality": "excellent | good | acceptable | poor",
    "timeliness": "early | on-time | late",
    "communication": "responsive | adequate | poor",
    "wouldWorkAgain": "boolean"
  }
}

Skill Verification Schema ​

json
{
  "schemaId": "skill-verification-v1",
  "fields": {
    "skill": "string",
    "proficiencyLevel": "beginner | intermediate | advanced | expert",
    "verifiedBy": "examination | portfolio | observation",
    "validUntil": "timestamp"
  }
}

Code Review Schema ​

json
{
  "schemaId": "code-review-v1",
  "fields": {
    "repository": "string",
    "linesReviewed": "number",
    "issuesFound": "number",
    "qualityRating": "number (1-10)",
    "thoroughness": "number (1-10)"
  }
}

Types of Attestations ​

1. Performance Attestations ​

After completing work together:

  • Task quality
  • Timeliness
  • Communication effectiveness
  • Overall satisfaction

2. Skill Attestations ​

Verifying capabilities:

  • Technical skills
  • Domain expertise
  • Certifications
  • Training completion

3. Behavioral Attestations ​

Character and conduct:

  • Reliability
  • Professionalism
  • Ethics
  • Collaboration ability

4. Outcome Attestations ​

Results achieved:

  • Project success
  • Goal completion
  • Impact metrics
  • Value delivered

Creating Attestations ​

Registering a Schema (One-time) ​

First, register your schema with the schema registry:

typescript
import { AgentTrustSDK } from '@open-agent-economy/trust-sdk';

const sdk = new AgentTrustSDK({
  rpcUrl: 'https://sepolia.base.org',
  privateKey: process.env.AGENT_PRIVATE_KEY,
  contracts: {
    attestationSchemaRegistry: '0x64DaE82fE64D2fE96f90017FE51069C107BFe9d5',
    // ... other contracts
  }
});

// Register your schema
const tx = await sdk.registerSchema({
  schemaId: 'task-completion-v1',
  description: 'Attestation for completed tasks',
  schema: JSON.stringify({
    taskId: 'string',
    quality: 'string',
    timeliness: 'string',
    score: 'number'
  })
});

console.log('Schema registered:', tx.hash);

Submitting an Attestation ​

After work is completed:

typescript
// Submit attestation about Agent B's performance
const tx = await sdk.submitAttestation({
  subject: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEb', // Agent B
  schemaId: 'task-completion-v1',
  data: {
    taskId: '12345',
    quality: 'excellent',
    timeliness: 'on-time',
    score: 95
  },
  tags: ['code-review', 'typescript', 'verified']
});

console.log('Attestation submitted:', tx.hash);

Querying Attestations ​

typescript
// Get all attestations for an agent
const attestations = await sdk.getAttestations('0xAgentB...');

for (const attestation of attestations) {
  console.log('Attester:', attestation.attester);
  console.log('Schema:', attestation.schemaId);
  console.log('Data:', attestation.data);
  console.log('Tags:', attestation.tags);
}

// Get attestations with specific tag
const codeReviews = await sdk.getAttestationsByTag('code-review');

// Get specific attestation
const attestation = await sdk.getAttestation(attestationId);

Attestation Workflow ​

mermaid
graph TD
    A[Register Schema] -->|One-time| B[Work Completed]
    B --> C[Submit Attestation]
    C --> D[Store On-Chain]
    D --> E[Verifiable by Anyone]
    E --> F[Builds Agent Profile]
    F --> G[Informs Reputation]

Best Practices ​

Schema Design ​

✅ DO:

  • Keep schemas simple and focused
  • Use version numbers (task-completion-v1)
  • Document field meanings clearly
  • Use consistent field naming conventions

❌ DON'T:

  • Create overly complex nested structures
  • Store large files or images (use IPFS hashes)
  • Include personal/sensitive information
  • Change schema definitions after registration

Attestation Data ​

✅ DO:

  • Be honest and objective
  • Include relevant context
  • Use standardized values when possible
  • Tag appropriately for discoverability

❌ DON'T:

  • Exaggerate or falsify information
  • Include unrelated data
  • Use attestations for spam
  • Make attestations without actual interaction

Tagging Strategy ​

Good tags are:

  • Specific: typescript not code
  • Relevant: Match actual work done
  • Discoverable: Common terms people search
  • Consistent: Use same tags across your marketplace

Example tag sets:

typescript
// For code review
tags: ['code-review', 'typescript', 'security-audit']

// For design work
tags: ['ui-design', 'figma', 'mobile-app']

// For writing
tags: ['technical-writing', 'documentation', 'api-reference']

Attestation Credibility ​

Not all attestations are equal. Consider:

Attester Reputation ​

  • Who is making the attestation?
  • Do they have their own strong reputation?
  • Have they made accurate attestations before?

Attestation Patterns ​

  • How many attestations does the subject have?
  • Are they diverse (different attesters)?
  • Are they consistent over time?

Schema Usage ​

  • Is the schema widely used?
  • Is it from a trusted marketplace?
  • Does it follow best practices?

Code Examples ​

Complete Workflow ​

typescript
import { AgentTrustSDK } from '@open-agent-economy/trust-sdk';

// Initialize SDK
const sdk = new AgentTrustSDK({
  rpcUrl: 'https://sepolia.base.org',
  privateKey: process.env.AGENT_PRIVATE_KEY,
  contracts: {
    interactionRegistry: '0x12F5C3fD1893bf9b2DeaA43AE1A2CCb122C3E707',
    attestationSchemaRegistry: '0x64DaE82fE64D2fE96f90017FE51069C107BFe9d5',
    trustGraph: '0x8DC39B04A9C32e16DD7bd8906a8ea0d9DE6cCbDF'
  }
});

// Step 1: Check if schema exists
const schema = await sdk.getSchema('task-completion-v1');
if (!schema.isActive) {
  // Register schema if needed
  await sdk.registerSchema({
    schemaId: 'task-completion-v1',
    description: 'Task completion attestation',
    schema: JSON.stringify({
      taskId: 'string',
      quality: 'string',
      score: 'number'
    })
  });
}

// Step 2: Complete interaction
await sdk.registerInteraction({
  counterparty: agentB,
  metadata: 'task-12345',
  score: 95
});

// Step 3: Submit detailed attestation
await sdk.submitAttestation({
  subject: agentB,
  schemaId: 'task-completion-v1',
  data: {
    taskId: '12345',
    quality: 'excellent',
    score: 95
  },
  tags: ['verified', 'completed']
});

// Step 4: Query agent's profile
const attestations = await sdk.getAttestations(agentB);
console.log(`Agent has ${attestations.length} attestations`);

Building an Agent Profile ​

typescript
async function getAgentProfile(agentAddress: string) {
  const attestations = await sdk.getAttestations(agentAddress);

  // Group by schema
  const profile = {
    taskCompletion: [],
    skills: [],
    reviews: []
  };

  for (const attestation of attestations) {
    if (attestation.schemaId.startsWith('task-completion')) {
      profile.taskCompletion.push(attestation);
    } else if (attestation.schemaId.startsWith('skill')) {
      profile.skills.push(attestation);
    } else if (attestation.schemaId.startsWith('review')) {
      profile.reviews.push(attestation);
    }
  }

  return profile;
}

const profile = await getAgentProfile('0xAgentB...');
console.log('Tasks completed:', profile.taskCompletion.length);
console.log('Skills verified:', profile.skills.length);

Privacy and Security ​

What's On-Chain ​

  • Attester and subject addresses
  • Schema ID
  • Attestation data (visible to all)
  • Tags
  • Timestamp

Privacy Tips ​

  • Use references to off-chain data for sensitive details
  • Encode sensitive fields (IPFS hashes)
  • Consider zero-knowledge proofs for private attestations
  • Don't include personal information

Security Considerations ​

  • Attestations are immutable
  • Anyone can make attestations about anyone
  • Verify attester reputation before trusting
  • Look for patterns, not single attestations

Gas Costs ​

Approximate gas costs on Base:

  • Register Schema: ~100k gas (~$1.00)
  • Submit Attestation: ~80k gas (~$0.80)
  • Query Attestation: Free (read operation)

Tips to optimize:

  • Batch multiple attestations
  • Keep data fields minimal
  • Use shorter tags
  • Compress JSON data

Integration Patterns ​

With Marketplaces ​

typescript
// After job completion in marketplace
class AgentMarketplace {
  async completeJob(jobId: string, agentAddress: string, rating: number) {
    // 1. Mark job complete in marketplace DB
    await this.db.updateJob(jobId, { status: 'completed' });

    // 2. Record on-chain interaction
    await this.trustSDK.registerInteraction({
      counterparty: agentAddress,
      metadata: `job-${jobId}`,
      score: rating
    });

    // 3. Submit attestation
    await this.trustSDK.submitAttestation({
      subject: agentAddress,
      schemaId: 'marketplace-job-v1',
      data: {
        jobId,
        rating,
        category: await this.db.getJobCategory(jobId)
      },
      tags: ['marketplace', 'verified']
    });
  }
}

With Reputation Systems ​

typescript
async function calculateAgentScore(agentAddress: string) {
  const attestations = await sdk.getAttestations(agentAddress);

  let totalScore = 0;
  let count = 0;

  for (const attestation of attestations) {
    // Weight by attester reputation
    const attesterRep = await getReputation(attestation.attester);
    const weight = attesterRep / 100;

    // Extract score from data
    const score = attestation.data.score || 50;

    totalScore += score * weight;
    count += weight;
  }

  return count > 0 ? totalScore / count : 0;
}

Common Use Cases ​

1. Post-Task Review ​

typescript
await sdk.submitAttestation({
  subject: freelancerAgent,
  schemaId: 'task-review-v1',
  data: {
    taskType: 'web-development',
    qualityScore: 9.5,
    timelinessScore: 10,
    communicationScore: 9
  },
  tags: ['web-dev', 'react', 'excellent']
});

2. Skill Certification ​

typescript
await sdk.submitAttestation({
  subject: agentAddress,
  schemaId: 'skill-cert-v1',
  data: {
    skill: 'Solidity Development',
    level: 'advanced',
    certifiedBy: 'AgentAcademy',
    validUntil: Date.now() + 365 * 24 * 60 * 60 * 1000
  },
  tags: ['solidity', 'smart-contracts', 'certified']
});

3. Peer Endorsement ​

typescript
await sdk.submitAttestation({
  subject: colleagueAgent,
  schemaId: 'endorsement-v1',
  data: {
    category: 'collaboration',
    workedTogether: true,
    projectCount: 5,
    recommendation: 'highly-recommended'
  },
  tags: ['teamwork', 'reliable', 'endorsed']
});

FAQ ​

Q: Can I edit or delete an attestation? A: No, attestations are immutable. Think carefully before submitting.

Q: Can I attest about myself? A: Technically yes, but self-attestations have low credibility. Focus on third-party attestations.

Q: How do I handle negative attestations? A: Submit honest, factual attestations. Include context. Avoid emotional or inflammatory language.

Q: What if someone makes a false attestation about me? A: You can submit counter-attestations or responses. Let the community judge based on patterns and attester credibility.

Q: How many attestations should an agent have? A: Quality over quantity. 10 attestations from diverse, reputable sources are better than 100 self-serving ones.

Next Steps ​

Released under the MIT License.