Inferensys

Prompt

Partial Result Synthesis Prompt

A practical prompt playbook for orchestration engineers merging incomplete outputs from multiple failed or timed-out agents into a single, trustworthy response.
Developer demonstrating multi-agent tool use, agent tool selection interface on laptop, casual tech demo moment.
PROMPT PLAYBOOK

When to Use This Prompt

Identify the ideal conditions, required inputs, and failure modes that make the Partial Result Synthesis Prompt the right tool for the job.

This prompt is designed for orchestration engineers and SRE teams managing multi-agent workflows where one or more agents have failed, timed out, or returned degraded results. The primary job-to-be-done is producing a single, coherent, and honest consolidated response from fragmented partial outputs. The ideal user is a platform engineer building a supervisor or arbitrator agent that must never silently hallucinate content for missing sections. Required context includes the original user request, the list of agents and their assigned subtasks, the partial outputs (including error messages or timeout signals), and a defined output schema with confidence scoring. Use this when you need to merge what you have, document what is missing, and assign explicit confidence levels so downstream systems or human reviewers can make informed decisions.

Do not use this prompt when all agents have completed their tasks successfully and you simply need to concatenate results—a standard assembly prompt is sufficient. Avoid it when the failure is a critical safety or compliance violation that requires immediate human intervention without any AI-generated summary. This prompt is also inappropriate when the partial results are so corrupted or contradictory that any synthesis would be misleading; in those cases, escalate the entire context to a human operator. The prompt assumes you have at least one partial result to work with. If every agent has failed with no output, this prompt will correctly produce a document consisting entirely of 'not completed' markers, which may be the desired behavior but offers little value beyond a structured error report.

Before wiring this into your application, ensure you have a robust validation layer that checks the output against the expected schema, verifies that confidence scores are present for every section, and confirms that no fabricated content has been injected into sections marked as 'not completed.' In high-risk domains, always route the synthesized output to a human review queue before it reaches the end user. The next step is to pair this prompt with the Partial Result Validation Prompt to automatically gate whether the synthesis is safe to forward.

PRACTICAL GUARDRAILS

Use Case Fit

Where the Partial Result Synthesis Prompt works and where it introduces unacceptable risk. Use this to decide whether to deploy the prompt or choose a different fallback strategy.

01

Good Fit: Multi-Agent Orchestration

Use when: multiple specialized agents have produced partial outputs and at least one agent failed or timed out. The prompt merges completed sections, marks gaps, and assigns confidence scores. Guardrail: always validate that the synthesizer does not fabricate content for missing sections by running the dedicated hallucination eval before forwarding output downstream.

02

Bad Fit: Single-Agent Timeouts

Avoid when: a single agent fails without producing any structured partial output. The synthesis prompt requires completed fragments to merge; empty input produces fabricated structure. Guardrail: route single-agent failures to a retry or escalation prompt instead. Only invoke synthesis when at least one agent returned a valid partial result.

03

Required Inputs

What you need: a list of agent outputs with status markers (completed, failed, timed_out), the original user request, and the expected output schema. Guardrail: strip any raw error traces or internal tool-call logs from agent outputs before passing them to the synthesizer. The prompt should see only the user-facing partial results and status flags.

04

Operational Risk: Silent Hallucination

Risk: the synthesizer fills missing sections with plausible but fabricated content to produce a 'complete-looking' response. This is the most dangerous failure mode in production. Guardrail: require explicit 'NOT_COMPLETED' markers in the output schema, run a post-synthesis validator that checks every section against its source agent output, and escalate to human review if any completed section lacks a source trace.

05

Operational Risk: Confidence Inflation

Risk: the synthesizer assigns high confidence scores to merged sections that came from agents with known tool failures or stale context. Guardrail: pass each agent's failure context and tool-call status into the synthesis prompt. Require the prompt to downgrade confidence when the source agent experienced a tool failure, even if its text output looks plausible.

06

When to Skip Synthesis Entirely

Avoid when: the downstream consumer cannot handle partial responses or the user expects a definitive answer. Synthesis is for graceful degradation, not for hiding failures. Guardrail: if the use case requires 100% completeness, route to a human fallback queue instead of synthesizing partial results. Document the degradation decision in the system audit log.

PROMPT PLAYBOOK

Copy-Ready Prompt Template

A reusable prompt for merging incomplete outputs from multiple agents into a consolidated, honest response with confidence scores and explicit gap markers.

This prompt template is designed to be the final synthesis step in an orchestration layer. It receives the outputs of multiple agents, some of which may have failed, timed out, or returned partial results. The prompt's job is not to fabricate missing data but to produce a coherent, structured summary that clearly separates completed work from gaps. Wire this into your application after collecting all agent outputs and before returning to the user or downstream system.

text
You are a synthesis engine responsible for merging partial outputs from multiple specialized agents into a single consolidated response. Your primary directive is accuracy and honesty: you must never invent, guess, or hallucinate information for sections where an agent failed or provided no output.

## INPUT
You will receive a collection of agent outputs. Each output includes:
- agent_id: A unique identifier for the agent.
- status: One of 'completed', 'partial', 'failed', or 'timed_out'.
- output: The raw text or structured data produced by the agent. This field may be empty or contain an error message if the status is not 'completed'.
- error_message: A description of the failure if status is 'failed' or 'timed_out'.

[AGENT_OUTPUTS]

## OUTPUT SCHEMA
Return a single valid JSON object conforming to this structure:
{
  "overall_status": "partial" | "complete" | "failed",
  "summary": "A concise, high-level summary of what was accomplished and what is missing. Do not mention specific agents by ID; describe the work product.",
  "sections": [
    {
      "section_name": "A descriptive name for this part of the response",
      "status": "completed" | "partial" | "missing",
      "confidence": 0.0-1.0,
      "content": "The synthesized content for this section. If status is 'missing', this must be an explicit statement that the information is unavailable, e.g., 'This analysis could not be completed because the responsible agent timed out.'",
      "source_agent_id": "The agent_id that provided the primary input for this section",
      "gap_description": "If status is not 'completed', a clear explanation of what is missing and why."
    }
  ],
  "gaps_summary": [
    "A list of human-readable descriptions of each significant gap in the final output."
  ],
  "user_facing_message": "A message suitable for display to an end-user, explaining the state of the response without exposing internal agent details."
}

## CONSTRAINTS
[CONSTRAINTS]

## EXAMPLES
[EXAMPLES]

## INSTRUCTIONS
1. Review all agent outputs. Identify which agents completed successfully and which did not.
2. For completed agents, synthesize their output into the appropriate sections. Preserve factual accuracy.
3. For failed or timed-out agents, create a section with status 'missing' or 'partial'. The content field must explicitly state that the information is unavailable. Reference the gap_description for details.
4. If an agent returned a partial output, include what is usable and clearly mark the incomplete parts.
5. Calculate a confidence score for each section based on the agent's status and the coherence of its output. A completed agent with clear output should have high confidence (0.9-1.0). A partial agent should have lower confidence (0.4-0.7). A missing section has a confidence of 0.0.
6. Set the overall_status to 'complete' only if all agents completed successfully. Use 'partial' if some agents failed or timed out. Use 'failed' if no usable output was produced.
7. The user_facing_message should be polite, honest, and avoid technical jargon like 'agent failure' or 'timeout'. Frame it in terms of what information is ready and what requires further action.
8. Never fabricate data to fill a gap. If you are unsure about any detail, lower the confidence score and note the uncertainty.

To adapt this template, replace the placeholders with your specific context. [AGENT_OUTPUTS] should be populated programmatically with the raw results from your agent execution graph. [CONSTRAINTS] can include rules like maximum section count, forbidden topics, or required disclaimers. [EXAMPLES] should contain one or two few-shot demonstrations of correct synthesis, especially showing how to handle a 'missing' section without hallucination. Before deploying, run this prompt against a golden test set where you intentionally cause agent failures and verify that the output never contains fabricated data in the 'missing' sections. For high-risk domains, always route the final output through a human review step before displaying it to users.

IMPLEMENTATION TABLE

Prompt Variables

Required inputs for the Partial Result Synthesis Prompt. Each placeholder must be populated before the prompt is assembled and sent to the model. Missing or malformed variables are the most common cause of hallucinated completion markers.

PlaceholderPurposeExampleValidation Notes

[AGENT_OUTPUTS]

Collection of partial or failed outputs from each agent in the execution graph. Each entry must include agent ID, completion status, and raw output.

{ "agent_id": "research-agent-3", "status": "timeout", "output": { "findings": "Partial market data for Q3..." } }

Must be valid JSON array. Each object requires agent_id (string), status (enum: completed, timeout, failed, unavailable), and output (object or null). Reject if array is empty or missing status field.

[TASK_DESCRIPTION]

The original task or question that was assigned to the agent graph. Provides the synthesis target for the model.

"Analyze competitive landscape for Product X in the European market and provide a go-to-market recommendation."

Must be non-empty string. Should match the original task, not a rephrased version. Null or empty string causes the model to fabricate a task context.

[REQUIRED_SECTIONS]

Ordered list of sections or subtasks that were expected from the full agent execution. Used to detect gaps.

["Market Size Estimate", "Competitor Profiles", "Pricing Analysis", "Regulatory Risks", "Recommendation"]

Must be a JSON array of strings. Each string must be a distinct section name. Duplicate section names cause gap-detection errors. Empty array allowed only if task had no predefined structure.

[CONFIDENCE_THRESHOLD]

Minimum confidence score (0.0 to 1.0) required to mark a section as completed rather than degraded. Sections below this threshold receive explicit gap markers.

0.7

Must be a float between 0.0 and 1.0 inclusive. Values outside range cause all-or-nothing confidence assignment. Default to 0.7 if not specified but log a warning.

[OUTPUT_SCHEMA]

Expected JSON schema for the synthesized output. Defines the structure the model must produce, including required fields for confidence, gaps, and status markers.

{ "sections": [{ "name": "string", "status": "completed|degraded|missing", "confidence": 0.0-1.0, "content": "string", "source_agents": ["string"] }], "overall_confidence": 0.0-1.0, "gap_summary": "string" }

Must be a valid JSON Schema object or a concise field description. Schema check: verify output contains sections array, overall_confidence, and gap_summary. Missing gap_summary is a critical failure for this prompt.

[FAILURE_CONTEXT]

Metadata about why agents failed, including error types, timeout durations, and unavailable agent IDs. Prevents the model from guessing failure reasons.

{ "failed_agents": ["research-agent-3"], "failure_reasons": { "research-agent-3": "timeout after 30s" }, "unavailable_agents": ["pricing-agent-1"] }

Must be a JSON object with at least one of failed_agents or unavailable_agents arrays. Null allowed only if no failures occurred (but then this prompt is unnecessary). Missing failure_context causes hallucinated failure explanations.

[HALLUCINATION_CONSTRAINTS]

Explicit rules for what the model must not do: invent completed sections, fabricate agent outputs, or fill gaps with plausible-sounding content.

"Do not generate content for sections marked as missing. Do not invent data that does not appear in the agent outputs. Use 'NOT COMPLETED' for any section without source data."

Must be a non-empty string. Should be appended verbatim to the system prompt. Weak or missing constraints are the primary cause of hallucination in partial-result synthesis. Test with a known-missing section to verify compliance.

PROMPT PLAYBOOK

Implementation Harness Notes

How to wire the Partial Result Synthesis Prompt into an orchestration layer with validation, retries, and safe handoff.

The Partial Result Synthesis Prompt is designed to be called by an orchestrator after one or more downstream agents have failed, timed out, or returned incomplete results. The orchestrator should collect all partial agent outputs, failure metadata (error codes, timeout durations, last successful step), and the original user intent into a structured context object before invoking this prompt. The prompt itself is stateless—it does not retry failed agents or fetch missing data. Its sole job is to merge what exists into a coherent, honest, and machine-readable synthesis that downstream systems or human reviewers can act on. This means the calling harness must own the retry policy, the timeout budget, and the decision about when to stop waiting for agents and invoke synthesis.

Wire the prompt into your agent framework as a terminal fallback step in any multi-agent graph or DAG. When a node fails or a parallel agent group returns with a failure count above a configured threshold, the orchestrator should: (1) collect all partial outputs and error metadata into a partial_results array, (2) attach the original user request and any session context, (3) call the synthesis prompt with a strict [OUTPUT_SCHEMA] that includes completed_sections, missing_sections, confidence_scores, and gap_documentation, and (4) validate the returned JSON against that schema before forwarding it. If validation fails, retry once with the validation error injected into [CONSTRAINTS]. If the retry also fails, log the raw output and escalate to a human reviewer with a structured handoff payload. Do not silently forward unvalidated synthesis output to users or downstream agents—hallucinated completions in missing sections are the primary failure mode here.

For production reliability, instrument the synthesis step with the following checks: confirm that every section marked completed has a non-null confidence_score between 0.0 and 1.0; confirm that every section marked missing has an explicit gap_documentation entry explaining what was not completed and why; and confirm that no section appears in both lists. Use a lightweight JSON Schema validator (such as ajv in Node.js or pydantic in Python) as a post-processing gate. If the synthesis output will be shown to end users, wrap it in a human-readable template that clearly separates completed content from gap notices—never present a raw synthesis payload as a final user-facing answer. For high-stakes domains (healthcare, finance, legal), require human approval on any synthesis where the ratio of missing sections to completed sections exceeds a configured threshold, or where any individual section confidence falls below 0.7.

IMPLEMENTATION TABLE

Expected Output Contract

Defines the schema, types, and validation rules for the consolidated response produced by the Partial Result Synthesis Prompt. Use this contract to parse, validate, and route the output in your orchestration harness.

Field or ElementType or FormatRequiredValidation Rule

synthesis_id

string (UUID v4)

Must parse as valid UUID v4. Reject if missing or malformed.

overall_status

enum: complete | partial | failed

Must match one of the three allowed values. If 'complete', all expected sections must be present.

sections

array of objects

Must be a non-empty array. Each element must conform to the section object schema defined below.

sections[].agent_id

string

Must match the agent identifier from the orchestration request. Null not allowed.

sections[].status

enum: completed | timed_out | tool_failure | unavailable | degraded

Must match one of the allowed statuses. If 'completed', the 'output' field is required.

sections[].output

object | null

Required when status is 'completed'. Must be valid JSON. Null allowed for non-completed statuses.

sections[].confidence

number (0.0 - 1.0)

Must be a float between 0.0 and 1.0 inclusive. Confidence must be 0.0 for 'unavailable' status.

sections[].gap_notes

string | null

Required when status is not 'completed'. Must describe what is missing and why. Null allowed for 'completed' status.

sections[].evidence_summary

string

Must be a non-empty string summarizing the source data or partial results received. Must not fabricate details for missing sections.

generated_at

string (ISO 8601)

Must parse as a valid ISO 8601 datetime in UTC. Reject if in the future by more than 5 minutes.

PRACTICAL GUARDRAILS

Common Failure Modes

Partial result synthesis is inherently risky. The model is asked to construct a coherent whole from incomplete parts. These are the most common ways it breaks and how to prevent them in production.

01

Hallucinating Missing Sections

What to watch: The model fills gaps with plausible-sounding but fabricated content instead of marking sections as 'not completed.' This is the most dangerous failure mode because it produces output that looks complete but is untrustworthy. Guardrail: Require explicit [NOT_COMPLETED] markers in the output schema and use a strict validator that rejects any section lacking a completion status. Add a system instruction: 'Never invent content for sections marked as incomplete by upstream agents.'

02

Confidence Score Inflation

What to watch: The model assigns high confidence scores to synthesized output even when the underlying agent results were low-confidence or missing. This misleads downstream consumers who rely on confidence signals for routing or escalation. Guardrail: Calculate a weighted confidence floor from input agent scores before synthesis. Include a rule in the prompt: 'The overall confidence score must not exceed the lowest confidence score among contributing agents unless independently verified.'

03

Silent Context Contamination

What to watch: Failed or timed-out agents may return partial state, error messages, or debugging artifacts that leak into the synthesized output. The model treats error text as valid content and weaves it into the final response. Guardrail: Pre-process all agent outputs with a sanitization step that strips error traces, stack traces, and internal agent state before passing to the synthesis prompt. Add a validation check for known error patterns in the final output.

04

Inconsistent Gap Documentation

What to watch: The model documents gaps inconsistently—some missing sections get detailed 'not completed' explanations while others are silently omitted. This creates an unpredictable output shape that breaks downstream parsers. Guardrail: Enforce a strict output schema where every expected section must appear with a completion status field. Use a post-generation validator that checks for the presence of all required section keys and rejects partial schemas.

05

Overconfident Synthesis from Single Source

What to watch: When only one agent succeeds and others fail, the model treats the single successful result as the complete answer without acknowledging the missing perspectives. This produces a one-sided synthesis that reads as authoritative. Guardrail: Include a 'contributing agents' field in the output that lists which agents provided input and which were unavailable. Add an instruction: 'If fewer than [MIN_AGENTS] agents contributed, flag the output as DEGRADED and reduce the overall confidence score by at least 0.3.'

06

Temporal Inconsistency Across Partial Results

What to watch: Agents may complete at different times with stale or conflicting temporal context. The synthesis merges results without detecting that Agent A's output references a state that Agent B's output has already superseded. Guardrail: Include a timestamp or version marker in every agent's output contract. Add a synthesis instruction: 'Compare timestamps across agent results. If any result is older than [STALENESS_THRESHOLD], flag it as STALE and reduce its weight in the synthesis.'

IMPLEMENTATION TABLE

Evaluation Rubric

Use this rubric to test partial result synthesis quality before shipping. Each criterion targets a specific failure mode: hallucination in missing sections, incorrect confidence scoring, or misleading completeness signals.

CriterionPass StandardFailure SignalTest Method

Gap Documentation Completeness

Every agent task that failed or timed out is listed with an explicit 'not completed' marker and a brief reason

Missing agent failures are absent from the output; failed sections appear as if they succeeded

Diff the input failure list against the output's gap documentation; require 100% recall of failed tasks

Hallucination Prevention in Missing Sections

Sections marked as incomplete contain zero fabricated content, only the gap reason and a null or empty payload

Incomplete sections contain plausible but unsupported content, statistics, or conclusions

Spot-check 3 incomplete sections per output; assert payload is null, empty, or exactly the gap reason string

Confidence Score Accuracy

Each completed section has a confidence score between 0.0 and 1.0 that correlates with evidence availability and agent completion status

Confidence scores are uniformly high despite known failures, or scores are missing for completed sections

Correlate confidence scores with known failure inputs; assert failed-agent sections score below 0.3, fully-successful sections above 0.7

Completed vs. Incomplete Boundary Clarity

Output clearly separates completed sections from incomplete sections with distinct formatting or a dedicated 'gaps' block

Completed and incomplete results are interleaved without clear demarcation, making it hard to distinguish reliable from unreliable content

Parse output structure; assert existence of a dedicated gaps array or section with no completed content mixed in

Source Attribution Preservation

All completed content retains citations or source references from the original agent outputs; no sources are fabricated for incomplete sections

Citations appear for content in sections where the source agent failed, or original citations are dropped from completed sections

Extract all citations; cross-reference against input agent outputs; assert zero citations map to failed agents

Consolidation Without Distortion

Merged content from multiple successful agents preserves original meaning without introducing contradictions or smoothing away disagreements

Disagreements between successful agents are silently resolved or rewritten to appear consistent

Compare merged output against individual agent outputs; flag any resolution of conflicting claims without explicit notation

User-Facing Degradation Notice Quality

Output includes a plain-language summary of what is missing, why, and what the user should do next, without technical jargon

Degradation notice is absent, overly technical, or misleadingly optimistic about missing content

Human review: rate notice on clarity and actionability; require score of 4/5 or higher on a 5-point rubric

Schema Compliance Under Degradation

Output conforms to the defined [OUTPUT_SCHEMA] even when sections are incomplete, with null fields where data is unavailable

Output breaks schema by omitting required fields, changing types, or using placeholder strings instead of null for missing data

Validate output against [OUTPUT_SCHEMA] with a JSON Schema validator; assert zero schema violations

ADAPTATION OPTIONS

Adapt This Prompt

How to adapt

Start with the base prompt and a single orchestrator agent. Use a simple JSON schema with only sections, overall_confidence, and gaps. Skip the per-section confidence scoring and evidence linking. Run with a timeout of 30s per agent and collect whatever partial outputs arrive.

Watch for

  • The synthesizer hallucinating content for timed-out agents instead of marking sections as not_completed
  • Missing the gaps array entirely when all agents fail
  • Overly verbose gap descriptions that bury actionable information
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.