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+# Contributor Schema
+
+Contributors are people who have engaged with the knowledge base. A contributor profile is computed from attribution data across claims — not stored separately. This schema defines the profile structure and tier system.
+
+## Contributor Tiers
+
+Tiers determine how agents engage with a contributor. Tier is computed from contribution history, not self-declared.
+
+| Tier | Criteria | Agent Behavior |
+|------|----------|----------------|
+| **visitor** | No contributions. First interaction. | Orientation mode: "What are you working on?" → match to agent → surface provocative claims → invite engagement. |
+| **contributor** | ≥1 merged contribution (source, challenge, or claim) | Skip orientation. Reference their history. Engage with their specific expertise. "You challenged Rio's claim about Dutch auctions — that challenge is still standing. What are you working on now?" |
+| **veteran** | ≥10 merged contributions AND ≥1 surviving challenge or belief influence | Peer engagement. Reference shared history. Invite to specific KB gaps matching their expertise. Ask for their take on open questions. Deeper context per interaction. |
+
+**Tier transitions are automatic.** The system computes tier from contribution data. No manual promotion. No application process. Contribute, and the agents notice.
+
+## Profile Structure
+
+```yaml
+handle: "@naval"                    # primary identity (X handle preferred)
+tier: contributor                   # computed: visitor | contributor | veteran
+linked_identities:                  # other identities for the same person
+  - type: x
+    handle: "@naval"
+  - type: github
+    handle: "naval"
+  - type: email
+    handle: "naval@example.com"
+first_contribution: 2026-02-15
+latest_contribution: 2026-03-11
+
+# Role counts (from attribution frontmatter across all claims)
+roles:
+  sourcer: 12
+  extractor: 0
+  challenger: 3
+  synthesizer: 1
+  reviewer: 0
+
+# Weighted score (role_counts × contribution-weights.yaml)
+weighted_score: 5.4
+
+# CI components (from reward-mechanism.md)
+ci:
+  belief_movers: 0.0
+  challenge_champions: 2.1
+  connection_finders: 0.8
+  total: 1.22    # weighted sum per ci_weights
+
+# Domain footprint
+domains:
+  internet-finance: 8
+  grand-strategy: 5
+  ai-alignment: 3
+
+# Contribution highlights (for agent context loading)
+highlights:
+  - "Challenged futarchy redistribution claim — challenge survived 2 counter-attempts"
+  - "Sourced 5 Theia Research pieces that produced 12 claims"
+  - "Connected prediction market volume claim to AI alignment belief"
+
+# Contribution timeline (monthly granularity)
+timeline:
+  - month: "2026-02"
+    count: 3
+    domains: ["internet-finance"]
+  - month: "2026-03"
+    count: 13
+    domains: ["internet-finance", "grand-strategy"]
+```
+
+## Identity Resolution
+
+**Primary identity: X handle.** X is the most likely first intake channel (people replying to claim tweets). The X handle is the canonical contributor identity.
+
+**Linked identities:** A contributor may have multiple identities across platforms (X, GitHub, email, wallet). These link to a single profile. Identity linking happens:
+- Automatically: same X handle appears in `proposed_by` (source) and git commits
+- Manually: contributor requests linking via the website or direct engagement
+
+**Pseudonymous-first.** Contributors use handles, not legal names. A handle persists across all contributions and is the public-facing identity.
+
+## How Profiles Are Computed
+
+Profiles are **derived, not stored** as primary data. The primary data is attribution frontmatter on claims and sources.
+
+### Computation steps
+
+1. **Scan all claims** for `attribution` blocks (see `schemas/attribution.md`)
+2. **Scan all sources** for `proposed_by` field
+3. **Group by handle** — aggregate role counts, domains, dates
+4. **Apply weights** from `schemas/contribution-weights.yaml`
+5. **Compute tier** from criteria above
+6. **Generate highlights** — top 3 contributions by impact (belief changes, surviving challenges, cross-domain connections)
+
+### Build artifact
+
+The build pipeline produces `contributors.json` — a static file rebuilt on every merge to main. Agents and the website read this file. No runtime queries needed.
+
+For agent session loading, a **contributor card** (compact summary) is extracted:
+
+```
+@naval | contributor | 16 contributions across internet-finance, grand-strategy
+Highlights: challenged futarchy redistribution (survived), sourced 12 Theia claims
+Last active: 2026-03-11
+```
+
+This card is injected into the agent's context at session start. ~50 tokens per contributor — cheap enough to load for any known contributor.
+
+## Agent Context Loading
+
+When a known contributor engages:
+
+1. **Lookup:** Match their identity (X handle, email, etc.) against `contributors.json`
+2. **Load card:** Inject contributor card into agent system prompt
+3. **Adjust behavior:** Agent follows tier-appropriate engagement pattern (see tiers above)
+4. **Reference history:** Agent can cite specific contributions, surviving challenges, domain expertise
+
+When an unknown person engages:
+1. **Default to visitor tier**
+2. **Run orientation flow** (see CLAUDE.md visitor section)
+3. **After first contribution:** profile is created, tier updates to contributor on next merge
+
+## Person Entity Bridge
+
+When a contributor has enough contributions to warrant tracking as an entity, their person entity (`entities/{domain}/{handle}.md`) gains `contributor: true`. The person entity tracks public information (role, organizations, influence). The contributor profile tracks KB-specific contribution data. Both link to each other.
+
+## Governance
+
+- Profiles are computed, not editable. To change your profile, change the underlying attribution data (via PR).
+- Handle changes require updating attribution frontmatter across affected claims (PR review required).
+- Disputes about attribution are resolved through the normal PR process.
+- Contributor data is public. Contribution history is visible to all agents and users.