Querying
How to retrieve, resolve, and score entities to build trusted profiles from the graph.
Querying is the Read Path of the Fide Context Protocol. This page covers how applications retrieve, resolve, and score graph data.
Because FCP is distributed, querying is not just SELECT *. It follows a three-step flow:
- Retrieve & Resolve: Fetching statements and merging multiple IDs into one entity.
- Consensus: Aggregating trust signals to decide what is "true".
- Traverse: Following relationships to discover connected context.
1. Retrieve & Resolve
In FCP, an entity resolves to one Primary Fide ID under a chosen trust policy, while multiple external identifiers are linked as aliases through Alias Clustering (owl:sameAs).
Primary + Aliases Pattern
To make sense of the chaos, FCP relies on two concepts:
- Primary Fide ID: A stable, protocol-native identifier (e.g.
did:fide:0x10...) derived from a Genesis Statement. - Aliases: Other IDs (LinkedIn, X) linked via
owl:sameAs.
Where to Learn the Link Pattern
For the statement pattern that creates alias links, see Relationships: Alias Clustering (owl:sameAs).
2. Consensus (Scoring Trust)
Once you have the data, how do you know what is true?
FCP uses a Subjective Trust Model. The protocol provides the votes (Evaluations); YOU decide the count.
Consensus Depends on Evaluation Statements
Consensus requires querying evaluation statements, not just base attributes/relationships.
- Evaluation statement shape: Statement schema
- Evaluation method semantics: EvaluationMethod
- Signal issuance flow: Evaluating
The Ground Truth Formula
Ground Truth = Σ (Evaluator Verdict × Evaluator Weight)| Value | Status | Meaning |
|---|---|---|
> 0 | Verified | Positive agreement from trusted peers |
< 0 | Refuted | Negative findings (fraud, falsehood) |
= 0 | Contested | Conflicting opinions or no data |
Weighting Strategies
Evaluator weights are application-side logic. You choose who to trust:
Trust is earned by history.
- High Accuracy Peer = 1.0x
- New/Unknown Peer = 0.1x
- Known Spammer = -1.0x
Trust is earned by openness.
- White-box Method (Open Code) = 1.2x Boost
- Black-box Method (Hidden) = 0.8x Penalty
3. API Patterns
FCP supports standard patterns for accessing the resolved graph.
JSON-LD Response
All responses use JSON-LD with standard vocabulary prefixes (schema:, prov:, owl:, sec:) to ensure interoperability.
{
"@id": "did:fide:0x10...",
"schema:name": "Alice Johnson"
}Computed Fields Are Indexer-Specific
Consensus outputs (like a "trust score") are derived at query time from Evaluations, not standardized as a single core predicate in the protocol.
Next Steps
- Evaluating — Learn how to create the trust signals used in Consensus.
- Schema — Deep dive into the data patterns (Attributes vs Relationships).