Inferensys

Prompt

Source Credibility Weighted Synthesis Prompt

A practical prompt playbook for using Source Credibility Weighted Synthesis Prompt in production AI workflows.
Developer doing prompt engineering on laptop, prompt variations visible on screen, casual coding session.
PROMPT PLAYBOOK

When to Use This Prompt

Determines the ideal conditions, required inputs, and inappropriate use cases for the Source Credibility Weighted Synthesis Prompt.

This prompt is designed for AI platform teams that have already assigned authority or credibility scores to their retrieved sources and need the synthesis step to respect that ranking. The primary job-to-be-done is generating an answer that prioritizes high-credibility sources, downgrades or excludes low-credibility sources, and transparently explains its weighting decisions. The ideal user is a RAG pipeline architect or an AI engineer who controls the retrieval and scoring stages and now needs the generation stage to be evidence-weighting-aware. The required context is a pre-retrieved, pre-scored set of passages, each with a credibility score and source identifier, plus a user query that the answer must address.

You should use this prompt when your retrieval pipeline already produces a credibility score per passage—for example, a 0.0–1.0 authority rating from a domain-specific classifier, a recency-weighted trust score, or a human-curated source tier. The prompt assumes you have already completed retrieval and scoring; it does not perform search or assign credibility scores from scratch. It is particularly valuable in regulated or high-stakes domains (legal, financial, medical) where citing a low-authority source can cause compliance or trust failures. The prompt includes explicit instructions to explain weighting decisions, making it suitable for applications that require audit trails or user-facing transparency about why certain sources were relied upon more heavily.

Do not use this prompt if you lack source-level credibility metadata, if your retrieval set has not been pre-filtered for relevance, or if you need the model to perform the initial credibility assessment. This prompt is not a replacement for a retrieval step or a scoring model—it is a synthesis harness that consumes scored evidence. Avoid using it when all sources are equally credible, as the weighting instructions will add unnecessary complexity without improving output quality. For high-risk applications, always pair this prompt with a post-generation faithfulness verification step and human review for critical decisions. If your credibility scores are unreliable or uncalibrated, the prompt will faithfully amplify those errors, so validate your scoring pipeline before relying on weighted synthesis in production.

PRACTICAL GUARDRAILS

Use Case Fit

This prompt is designed for AI platform teams that have pre-assigned authority scores to sources. It works well when credibility signals are available and the goal is transparent, weighted synthesis. It fails when scores are missing, stale, or treated as absolute truth.

01

Good Fit: Pre-Scored Knowledge Bases

Use when: you have a curated knowledge base with authority scores (e.g., internal docs > vendor docs > forum posts). Guardrail: validate that scores are updated when sources change and that the scoring model is documented.

02

Bad Fit: Ad-Hoc Web Search

Avoid when: sources come from raw web search with no credibility metadata. The model will hallucinate authority rankings or treat all sources equally. Guardrail: use a separate source trustworthiness assessment prompt before this synthesis step.

03

Required Input: Authority Scores

Risk: without explicit scores, the model invents credibility rankings based on surface features like domain name or writing style. Guardrail: always pass scores as structured fields alongside each passage, and validate that every passage has a score before synthesis.

04

Operational Risk: Score Staleness

Risk: authority scores become outdated as sources change, leading to over-reliance on deprecated documents. Guardrail: implement score refresh pipelines with TTLs, and include recency as a secondary weighting factor in the prompt.

05

Operational Risk: Over-Deference to High Scores

Risk: the model may ignore relevant information from lower-scored sources even when high-scored sources are incomplete. Guardrail: instruct the model to include unique information from lower-credibility sources with explicit caveats rather than dropping it entirely.

06

Bad Fit: Single-Source Answers

Avoid when: only one source is available. Weighted synthesis adds no value and the credibility weighting logic may distort the answer. Guardrail: route single-source queries to a simpler grounded QA prompt instead.

PROMPT PLAYBOOK

Copy-Ready Prompt Template

A reusable prompt that synthesizes an answer from multiple sources, weighting contributions by pre-assigned authority scores.

This template is designed to be pasted into your system or user message. It instructs the model to generate a final answer that prioritizes information from high-credibility sources, downgrades or excludes low-credibility sources, and explains its weighting decisions. Replace the square-bracket placeholders with your specific inputs, output schema, and constraints before wiring it into your application.

text
You are an evidence synthesis engine. Your task is to produce a final answer to a user's question by combining information from multiple provided sources. Each source has a pre-assigned credibility score from 0.0 (untrustworthy) to 1.0 (fully authoritative).

# INPUT
User Question:
[USER_QUESTION]

Sources with Credibility Scores:
[SOURCES_JSON_ARRAY]

# INSTRUCTIONS
1. **Prioritize High-Credibility Sources:** Base your answer primarily on sources with a credibility score of [HIGH_CREDIBILITY_THRESHOLD] or higher. Use these sources as the foundation of your response.
2. **Downgrade or Exclude Low-Credibility Sources:** Information from sources with a score below [LOW_CREDIBILITY_THRESHOLD] should be treated as unreliable. Do not use it to form the core of your answer. If you must mention it, clearly flag it as low-credibility.
3. **Handle Conflicts:** If high-credibility sources disagree, present the conflicting viewpoints without fabricating a consensus. If a high-credibility source contradicts a low-credibility one, default to the high-credibility source.
4. **Explain Weighting:** In your reasoning, briefly note how the credibility scores influenced your synthesis. If you downgraded or excluded a source, explain why.
5. **Synthesize, Don't List:** Do not summarize each source individually. Weave the information into a single, coherent answer.

# OUTPUT FORMAT
You must respond with a single JSON object conforming to this schema:
[OUTPUT_SCHEMA]

# CONSTRAINTS
- Do not introduce any external knowledge not present in the provided sources.
- If no source meets the high-credibility threshold, state that a reliable answer cannot be provided and explain why.
- If the provided sources are insufficient to answer the question, set the `answerable` field to `false` and explain what is missing.

To adapt this template, replace [USER_QUESTION] with the user's query, and [SOURCES_JSON_ARRAY] with a JSON array of objects, each containing source_id, text, and credibility_score. Define [HIGH_CREDIBILITY_THRESHOLD] and [LOW_CREDIBILITY_THRESHOLD] based on your risk tolerance (e.g., 0.8 and 0.4). The [OUTPUT_SCHEMA] placeholder must be replaced with your exact JSON schema, including fields for the answer, weighting_rationale, and an answerable boolean. For high-stakes domains, ensure your application layer validates the output against this schema and logs any instances where the model fails to provide a weighting rationale or incorrectly marks a question as unanswerable.

IMPLEMENTATION TABLE

Prompt Variables

Placeholders required to make the Source Credibility Weighted Synthesis Prompt work reliably in a production RAG pipeline. Each variable must be populated before the prompt is assembled and sent to the model.

PlaceholderPurposeExampleValidation Notes

[QUERY]

The user question or task that requires evidence-weighted synthesis.

What are the long-term effects of the 2022 drought on California almond production?

Must be a non-empty string. Check for adversarial or off-topic queries before passing to the prompt.

[RETRIEVED_PASSAGES]

Array of source passages with pre-assigned credibility metadata.

[{"id":"src-1","text":"...","authority_score":0.92,"recency_score":0.85,"source_type":"peer-reviewed"}]

Must be a valid JSON array with at least one passage. Each passage object requires id, text, and authority_score fields. Reject if authority_score is missing or outside 0.0-1.0 range.

[CREDIBILITY_THRESHOLD]

Minimum authority_score a source must meet to be used as primary evidence. Sources below this threshold are downgraded or excluded.

0.7

Must be a float between 0.0 and 1.0. Default to 0.6 if not specified. Validate that threshold is not set so high that all sources are excluded.

[OUTPUT_SCHEMA]

Expected structure for the synthesized response, including answer, citations, credibility notes, and uncertainty.

{"answer":"string","citations":[{"source_id":"string","quote":"string"}],"credibility_notes":"string","uncertainty_level":"low|medium|high"}

Must be a valid JSON schema or type description. Parse check before prompt assembly. Reject schemas that lack citation or credibility fields.

[MAX_ANSWER_LENGTH]

Token or word limit for the synthesized answer to prevent verbose outputs in production.

500 words

Must be a positive integer with unit (tokens or words). Validate that limit is not below 50 words, which would prevent meaningful synthesis.

[EXCLUDED_SOURCE_TYPES]

Source types to exclude entirely from synthesis, regardless of authority_score.

["social-media","unverified-blog"]

Must be a valid JSON array of strings or null. If null, no source types are excluded. Validate against allowed source type taxonomy.

[REQUIRED_CITATION_COUNT]

Minimum number of distinct sources that must be cited in the answer. Triggers refusal if insufficient credible sources are available.

2

Must be a positive integer. Validate that count does not exceed available passages above credibility threshold. If it does, trigger evidence insufficiency refusal.

PROMPT PLAYBOOK

Implementation Harness Notes

How to wire the Source Credibility Weighted Synthesis Prompt into a production RAG pipeline with validation, retries, and audit logging.

This prompt is designed to sit downstream of a retrieval step and an authority-scoring step. Before calling the model, assemble the [SOURCES] array where each object contains the passage text, a pre-computed authority_score (e.g., 0.0–1.0), and a source_id. The prompt expects these scores to already exist—do not ask the model to compute credibility on the fly, as that introduces latency and inconsistency. The model's job is to weight its synthesis according to the scores you provide, not to re-evaluate source trustworthiness.

Wire the prompt into an application harness that validates the output schema before the response reaches the user. The expected output is a JSON object with answer, weighting_explanation, and excluded_sources fields. Implement a strict JSON schema validator in your application layer. If parsing fails, retry once with a repair prompt that includes the raw output and the schema. If the retry also fails, log the failure and fall back to a safe response that surfaces the raw sources without synthesis. For high-stakes domains, route outputs where excluded_sources contains high-authority sources to a human review queue—this indicates a possible scoring error upstream.

Log every invocation with the prompt_version, source_ids, authority_scores, output, and validator_result. This audit trail is essential for debugging credibility-weighting failures. Common failure modes include the model ignoring low-authority sources entirely when they contain critical context, or over-weighting a single high-authority source and producing a one-sided answer. Use eval assertions to check that the weighting_explanation references specific scores and that excluded sources are genuinely low-authority. Run a periodic eval sweep with synthetic source sets where the correct weighting is known to detect drift in model behavior.

IMPLEMENTATION TABLE

Expected Output Contract

Defines the structure, types, and validation rules for the Source Credibility Weighted Synthesis output. Use this contract to parse the model response, validate correctness before user delivery, and trigger repair or retry on failure.

Field or ElementType or FormatRequiredValidation Rule

synthesis_answer

string

Must be non-empty. Must not contain claims directly attributed to sources with authority_score < [MIN_AUTHORITY_THRESHOLD]. Check via substring match against low-authority source text.

weighting_rationale

array of objects

Array length must equal number of provided sources. Each object must contain source_id (string, matches input), authority_score (number, matches input), and contribution_summary (string, non-empty).

source_id

string

Must exactly match a source_id from the [SOURCES] input array. Regex validation against input keys.

authority_score

number

Must be within 0.01 of the corresponding input authority_score for that source_id. Floating-point comparison with tolerance.

contribution_summary

string

Must be non-empty. Must describe how the source was used or explain why it was excluded. If excluded, must reference low authority_score as reason.

excluded_sources

array of strings

If present, each string must match a source_id from [SOURCES] with authority_score below [MIN_AUTHORITY_THRESHOLD]. If no sources excluded, field must be absent or empty array.

confidence_level

string

Must be one of: 'high', 'medium', 'low'. 'high' requires at least 2 sources above [HIGH_CONFIDENCE_AUTHORITY_CUTOFF] supporting the primary claim. 'low' required if any supporting source is below [MIN_AUTHORITY_THRESHOLD].

uncertainty_flags

array of strings

If confidence_level is 'medium' or 'low', this field is required and must contain at least one non-empty string describing a specific uncertainty. If confidence_level is 'high', field must be absent or empty array.

PRACTICAL GUARDRAILS

Common Failure Modes

What breaks first when synthesizing answers from sources with pre-assigned credibility scores, and how to guard against it.

01

Credibility Score Ignored in Synthesis

What to watch: The model treats all sources equally despite provided authority scores, giving equal weight to a peer-reviewed study and a social media post. Guardrail: Add an explicit instruction in the prompt to prioritize high-credibility sources and require a justification when a low-credibility source is used. Validate with an eval that checks if the answer's claims disproportionately rely on low-score sources.

02

Over-Deference to a Single High-Authority Source

What to watch: The model fixates on the highest-scored source and ignores corroborating or conflicting evidence from other reasonably credible sources, creating a false consensus. Guardrail: Instruct the model to synthesize across all sources above a minimum threshold, not just the top one. Include a test case with multiple high-credibility sources that disagree to ensure all perspectives are represented.

03

Silent Exclusion of Low-Credibility Sources

What to watch: The model completely omits information from lower-scored sources without explanation, potentially dropping unique factual details that aren't available elsewhere. Guardrail: Require the model to explicitly list which sources were downgraded or excluded and why, and to check if any excluded source contains unique information not covered by higher-credibility sources.

04

Credibility Score Leakage into Output

What to watch: The model's internal reasoning about source credibility bleeds into the user-facing answer, producing text like "Source A is more trustworthy than Source B" instead of a clean synthesis. Guardrail: Use a two-pass approach: first, generate the weighted synthesis; second, strip any meta-commentary about source quality from the final output. Validate with a regex check for credibility discussion in the answer.

05

Hallucinated Credibility Justifications

What to watch: When asked to explain its weighting decisions, the model fabricates reasons for why a source was prioritized or excluded, inventing details about the source's methodology or reputation. Guardrail: Constrain the model to only reference the provided credibility score and metadata fields when explaining weighting decisions. Add an eval that checks if any justification contains claims not present in the source metadata.

06

Score Threshold Brittleness

What to watch: A hard threshold for source inclusion (e.g., "only use sources with score > 0.7") causes erratic behavior when all sources fall just below or just above the cutoff. Guardrail: Use a tiered approach with soft boundaries:

IMPLEMENTATION TABLE

Evaluation Rubric

Use this rubric to test the quality of a Source Credibility Weighted Synthesis output before shipping. Each criterion targets a specific failure mode common in credibility-weighted generation.

CriterionPass StandardFailure SignalTest Method

Credibility Adherence

Claims from high-credibility sources appear prominently; low-credibility source claims are downgraded, qualified, or excluded per [CREDIBILITY_THRESHOLD].

A claim from a source below the [CREDIBILITY_THRESHOLD] appears without a qualifier or is given equal weight to a high-credibility source.

Parse output for source citations. For each cited claim, verify the source's authority score against [SOURCE_SCORES]. Flag any claim where score < [CREDIBILITY_THRESHOLD] and no downgrade language is present.

Weighting Transparency

The output includes a 'Weighting Rationale' section explaining why specific sources were prioritized or downgraded.

The 'Weighting Rationale' section is missing, empty, or contains only generic statements like 'sources were weighted by credibility' without naming specific sources or scores.

Schema check: confirm the [OUTPUT_SCHEMA] 'weighting_rationale' field is present and non-null. Content check: verify at least one source is mentioned by ID and its score is referenced.

Source Conflict Handling

When high-credibility sources disagree, the output explicitly notes the disagreement and presents both perspectives without fabricating consensus.

Conflicting evidence from two high-credibility sources is merged into a single, unified claim that misrepresents the disagreement.

Inject a test retrieval set with two high-credibility sources that contradict each other on a key fact. Assert the output contains a 'disagreement' flag or presents both claims separately.

Low-Credibility Source Exclusion

Sources scored below [EXCLUSION_THRESHOLD] are not cited or used to support any factual claim.

A source with a score of 0.1 appears in the citations or its claims are included in the final answer.

Parse the output's citation list. Cross-reference each cited source ID against [SOURCE_SCORES]. Assert no cited source has a score < [EXCLUSION_THRESHOLD].

Faithfulness to Source Content

Every factual claim in the answer is directly supported by the cited source passage. No claim is exaggerated or distorted.

The output states 'Source A claims X,' but the provided passage from Source A does not support X or states a weaker version of X.

Use an LLM-as-judge with the prompt: 'Does the claim [OUTPUT_CLAIM] accurately reflect the meaning of [SOURCE_PASSAGE]?' Require a score >= [FAITHFULNESS_THRESHOLD].

Uncertainty Calibration

Claims from moderate-credibility sources or areas of source disagreement are accompanied by uncertainty language (e.g., 'may,' 'suggests,' 'according to').

A claim from a source with a middling score (e.g., 0.6) is stated as an unqualified fact.

Regex search for uncertainty hedges near citations from sources with scores between [LOW_CREDIBILITY_THRESHOLD] and [HIGH_CREDIBILITY_THRESHOLD]. Flag if no hedge is found within the same sentence as the citation.

Abstention on Unsupported Topics

If no source meets the [CREDIBILITY_THRESHOLD] for a sub-question, the output explicitly states that credible evidence is insufficient rather than answering from excluded sources.

The output provides a confident answer to a sub-question where all available sources are below the [CREDIBILITY_THRESHOLD].

Provide a retrieval set where all sources for a specific sub-question are scored below [CREDIBILITY_THRESHOLD]. Assert the output contains a refusal or insufficiency statement for that sub-question.

Schema Compliance

The output is valid JSON matching the [OUTPUT_SCHEMA] exactly, with all required fields present and correctly typed.

The output is missing the 'credibility_summary' field, or the 'citations' array contains objects with string 'score' fields instead of numeric.

Validate the raw model output against the [OUTPUT_SCHEMA] using a JSON schema validator. Assert no validation errors are returned.

ADAPTATION OPTIONS

Adapt This Prompt

How to adapt

Use the base prompt with a simple JSON schema for credibility scores. Hardcode a small set of source authority tiers (e.g., high, medium, low) instead of a numeric scoring model. Skip the full eval harness and test with 3-5 hand-picked source sets.

code
[CREDIBILITY_TIERS]:
- high: peer-reviewed journals, official government publications, established industry standards bodies
- medium: reputable news outlets, vendor documentation, expert blog posts
- low: forums, social media, unverified personal sites

Watch for

  • The model ignoring tier distinctions and treating all sources equally
  • Overly verbose credibility explanations that bury the answer
  • No mechanism to detect when a low-credibility source is the only source for a critical fact
Prasad Kumkar

About the author

Prasad Kumkar

CEO & MD, Inference Systems

Prasad Kumkar is the CEO & MD of Inference Systems and writes about AI systems architecture, LLM infrastructure, model serving, evaluation, and production deployment. Over 5+ years, he has worked across computer vision models, L5 autonomous vehicle systems, and LLM research, with a focus on taking complex AI ideas into real-world engineering systems.

His work and writing cover AI systems, large language models, AI agents, multimodal systems, autonomous systems, inference optimization, RAG, evaluation, and production AI engineering.