19 September 2026 · ReAct × Clinical Trials × Retrieval

Can an AI agent search clinical-trial evidence without losing the source?

A 30-minute pack on source-aware agents, ClinicalTrials.gov, PubMed, deterministic analysis, query decomposition and evidence paths that survive into the final answer.

DifficultyC1
Time30 minutes
ArchitectureReAct + RAG
OutputSP retrieval agent

Why this reading

A good agent does not search everything the same way.

A new ClinAgent preprint combines ClinicalTrials.gov retrieval, PubMed search and Python analysis behind a ReAct agent. The key professional skill is source routing: decide what information is needed, choose the strongest source, use deterministic computation where appropriate, and preserve provenance.

For SP automation, the equivalent is question → source selection → tool → retrieved evidence → deterministic check → conclusion.

Reading order

Your 30-minute plan.

0–3 minPreview

Find the three tools available to ClinAgent.

3–14 minMain paper

ReAct, planning, tool selection, synthesis and evaluation.

14–20 minClinicalTrials.gov

See how registry facts become structured API records.

20–25 minNCBI

Compare trial-registry retrieval with literature retrieval.

25–30 minOutput

Design a source-aware SP retrieval agent.

Open-access sources

Agent research plus authoritative retrieval interfaces.

Brief background

Retrieval, synthesis and analysis are different operations.

Clinical-trial questions often cross registries and publications. The registry can establish registered study facts; PubMed can retrieve scientific literature; Python over structured records can calculate counts, proportions or comparisons reproducibly.

ReAct gives the agent a loop: reason → choose tool → retrieve → observe → reason again → answer. The model becomes an orchestrator rather than the sole store of facts.

For SP work, the same pattern routes standards questions to CDISC metadata, study rules to protocol/SAP, data questions to SDTM/ADaM, execution questions to logs, and calculations to deterministic code.

The final answer should preserve provenance: source identity, retrieval/version context, relevant field or evidence, and any calculation performed.

Key vocabulary

Fifteen terms for agentic information retrieval.

Term中文Meaning
agentic retrieval-augmented generation智能体检索增强生成A workflow in which an LLM actively chooses retrieval tools, inspects results, and iterates before answering.
ReAct paradigm推理-行动范式An agent pattern that alternates reasoning with actions such as searches or tool calls.
semi-structured data半结构化数据Data with recognizable fields and hierarchy but not a fully rigid tabular schema.
cross-source synthesis跨来源综合Combining evidence from different databases or information systems into one answer.
grounded response有依据的回答An answer tied to retrieved source evidence rather than generated from model memory alone.
tool selection工具选择Choosing the most appropriate external function or data source for a subtask.
query decomposition查询拆解Breaking a complex information need into smaller searchable questions.
multi-turn interaction多轮交互A conversation in which later questions depend on earlier context.
locally cached dataset本地缓存数据集A local copy of structured data used for faster or reproducible analysis.
registry record注册记录The structured public record describing a clinical study in a trial registry.
literature retrieval文献检索Systematic searching and fetching of scientific publications.
provenance来源谱系Information showing where a fact came from and how it was transformed.
source reconciliation来源核对Resolving differences between multiple sources describing the same study or fact.
planning quality规划质量How well an agent sequences subtasks and chooses tools before producing an answer.
tool-use efficiency工具使用效率How effectively an agent reaches a reliable answer without unnecessary calls or steps.

Useful phrases

Language for retrieval, evidence and provenance discussions.

  1. the answer should remain grounded in the retrieved record.
  2. the agent should choose a source based on the information need.
  3. registry data and published literature answer different questions.
  4. cross-source synthesis requires explicit provenance.
  5. a plausible summary is not enough if the supporting record cannot be recovered.
  6. query decomposition improves both retrieval quality and auditability.
  7. the agent should distinguish absence of evidence from evidence of absence.
  8. cached structured data can improve reproducibility for analytical queries.
  9. tool-use efficiency matters only after retrieval accuracy is established.
  10. the final answer should expose the evidence path, not hide it.

Comprehension

Five questions.

  1. Why does a clinical-trial information agent need more than one retrieval tool?
  2. How does a registry record differ from a PubMed article?
  3. Why is deterministic Python analysis useful for some questions?
  4. How does ReAct differ from one-shot generation?
  5. What provenance should survive when several sources support one answer?

Retelling

Say it three times.

  • 30 seconds · Reason → tool → observation → reason again.
  • 45 seconds · Why ClinicalTrials.gov, PubMed and Python are complementary.
  • 60 seconds · Apply source routing to an SDTM/ADaM/TFL agent.

5-minute output task

Design a source-aware SP retrieval agent.

  1. Minute 1: Choose one study-specific programming question.
  2. Minutes 2–3: Route subquestions to protocol/SAP, spec, CDISC, data and program/log sources.
  3. Minute 4: Identify what must be calculated deterministically.
  4. Minute 5: Explain how the final answer preserves its evidence path.

One sentence to keep

A reliable clinical-research agent should not merely know what to say; it should know which source to query, which tool to use, and how to preserve the evidence path behind every conclusion.