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How to Read AI Agent Papers: From CoT and WebGPT to ReAct

Follow the core methods first, then open later work only when its question matters.

How to Read AI Agent Papers: From CoT and WebGPT to ReAct

Bookmark this page. The paper-reading hub already has three reading paths. If you have just finished the ReAct family, this page shows how the classic papers connect and which note to open next.

This is not a new paper note, and it does not replace the six Paper Essence questions in each linked article. It only answers how the nodes connect, which control point changed, and which link to open next.

Ninety-second mental model

  1. CoT (Wei et al., 2022) = reason without touching an environment. WebGPT (Nakano et al., 2021) = act with little explicit verbal reasoning. ReAct is the merge: thought, action, and observation interleave in one trajectory.
  2. From ReAct the control point splits: how tools are learned (Toolformer), how experience is written across trials (Reflexion), how success is scored on real repos (SWE-bench), how a finite context window is paged (MemGPT).
  3. Gorilla and Indirect Prompt Injection extend the tool and retrieval sequence: after catalog-scale retrieve-and-call, retrieved or tool-returned text shares the instruction channel with the user prompt. Generative Agents adds the multi-agent memory branch.
  4. The hub agent-systems path follows the same order as this page: read the core methods first, then open 2025–26 work when its question matters. SWE-Bench ProMax’s 41.2% and later Letta product metrics do not belong in 2023/2024 tables.
  5. Sharing a family name is not the same contract: few-shot ReAct ≠ Argus runtime; Toolformer’s single API insert ≠ MidTool mid-training; SWE-bench 1.96% is a protocol, not a model-ability ceiling.

CoT and WebGPT both have notes on this site; this page only links them into one reading sequence.

The method map

Papers that already have notes on this site are not labeled separately on the diagram. MemGPT was added later: it decides what stays in or goes out when context runs short, and it was not in the earliest sketch.

flowchart TB
  CoT["CoT: writes the reasoning out, still cannot act"]
  WebGPT["WebGPT: can browse, barely thinks out loud"]
  CoT --> ReAct["ReAct: think, act, look, then think again"]
  WebGPT --> ReAct
  ReAct --> Toolformer["Toolformer: learns on its own where to call tools"]
  ReAct --> Reflexion["Reflexion: after failure, writes lessons in plain language for the next round"]
  ReAct --> SWEb["SWE-bench: real GitHub issues; passing tests means done"]
  ReAct --> MemGPT["MemGPT: when context runs out, decides what stays and what goes out"]
  ReAct --> GenAgents["Generative Agents: many agents in a sandbox observe, reflect, and replan"]
  Toolformer --> Gorilla["Gorilla: finds which API to call from a huge catalog"]
  Gorilla --> IPI["Indirect Prompt Injection: retrieved content can be treated as instructions"]

How to walk the map

Path A · Fastest: ReAct, then one child

  1. ReAct: lock the thought–action–observation contract first.
  2. Pick one child for the place you are actually stuck: tools → Toolformer; across-trial memory → Reflexion; real-issue evaluation → SWE-bench; context paging → MemGPT.
  3. Stop. Read later work only when you need the question it addresses.

Path B · Full classic sequence: CoT → WebGPT → ReAct → … → Generative Agents

Follow the core-method segment of the hub agent-systems path in three stages:

  1. CoTWebGPTReAct
  2. ToolformerGorillaIndirect Prompt Injection
  3. SWE-benchReflexionMemGPTGenerative Agents

Stop after those ten. Open 2025–26 work such as OSReward or Argus only when you need the question it addresses.

Path C · Pick the next paper from the job

Where the work is stuckStart with this paperCore question it extends
Teaching tools, or too many schemasGorillaMidTool, RAG-MCPToolformer → Gorilla: tool use across training, retrieve-and-call, and routing
Whether retrieved or tool-returned text shares the instruction channelIndirect Prompt Injection → when needed, AgentS4D, Trajectory Sentinel, A2EGorilla → IPI: retrieval and tool returns entering the prompt
Remembering after failure, or whether a score gain is retained experienceADIAS, PAST-BenchReflexion: how experience is written across trials
How memory supports planning and social behavior in a multi-agent sandboxGenerative Agents vs MemGPTObserve-reflect-plan memory stream ≠ single-agent OS paging
Whether large, multilingual refactors still count as successSWE-Bench ProMaxSWE-bench: what counts as coding success
Long-horizon runtime, authority, and rollbackArgusA ReAct loop is not a deployable control plane
The system searched but answered before reading evidenceBefore Reasoning Can FailReAct can search; it does not guarantee read-before-final

Node table: control point, one sentence, do-not-misread

NodeControl point changedOne sentenceLinkDo not misread
CoTWhether the prompt writes intermediate reasoningReason without touching an environmentAlready on this siteA frozen prompt, not an agent that acts
WebGPTWhether browser actions are used to answerAct with little explicit verbal reasoningAlready on this siteBrowsing commands are not ReAct thoughts
ReActWhether the next move is a sentence to oneself or a touch of the worldAdd thought to the action space and interleave with observationAlready on this siteA few-shot loop is not an agent runtime
ToolformerWhether a training string should insert one API callFilter self-supervised tool use with future-token lossAlready on this siteNext-token API ≠ MidTool mid-training
GorillaHow to retrieve and call over a huge API catalogAPIBench + RAT put document retrieval into finetuning and cut hallucinationAlready on this siteCore tool-use method; catalog retrieve+call does not establish MCP product behavior and is not MidTool
Indirect Prompt InjectionWhether retrieved or tool-returned text shares the instruction channel with the user promptUntrusted data enters the prompt via retrieval or tool returns; attackers can control the model indirectlyAlready on this site2023 threat-model evidence, not a Guard product SLA
ReflexionWhere verbal experience is written after failureFreeze weights; write verbal feedback into a short buffer; start the next trialAlready on this siteExtra retries are not parameter learning
SWE-benchWhat counts as coding successA real GitHub issue plus passing tests is resolveAlready on this site1.96% is a protocol, not a ceiling
MemGPTWho decides what pages in and out of a finite contextTreat the prompt as RAM and external memory as disk; page with functionsAlready on this siteExtra node, not in the original sketch; not enterprise ACL memory, and not Letta product metrics
Generative AgentsHow memory supports planning among many agents in a sandboxObservations to memory stream, periodic reflection, retrieval-conditioned planning; 25 agents in SmallvilleAlready on this siteNot MemGPT single-agent paging, and not production runtime
MidToolWhen tool affordances are taughtMove grounding and execution earlier into mid-trainingAlready on this siteA later method, not Toolformer’s loss filter
RAG-MCPHow to choose among too many tool schemasRetrieve candidate schemas, then let the executor callAlready on this siteA later routing method; retrieval is not authorization
ADIASWhat indexes repair progressAn issue ledger remembers what was tried and which intervention failedAlready on this siteA leaf; not Reflexion’s short buffer
PAST-BenchWhether a better score came from retained experiencePair persistence on/off; separate task score from mechanism evidenceAlready on this siteA leaf; the paper is an evaluation device, not a new memory-algorithm SOTA
SWE-Bench ProMaxThe denominator for large multilingual refactorsA later evaluation substrate, not “models improved 41 points on the same 2,294 instances”Already on this siteA leaf; 41.2% must not be written back into original SWE-bench tables
Before reasoning can failWhether a read happens after search and before finalA pre-evidence procedural failure, not a wrong answer after reading goldAlready on this siteA leaf; Read-Gate is not a substitute for retrieval quality
ArgusThe control plane for long-horizon workAuthority, verifier, rollback—not a longer promptAlready on this siteA leaf; a ReAct loop is not this runtime

What this page is not

  • It does not replace the six Paper Essence questions. Each linked note still has to carry: the problem, why the prior approach was insufficient, the core idea, how one input moves through the method, which evidence supports the headline, and where the claim stops. This page only orients.
  • It does not rewrite the spine. The 2026 CoT and WebGPT notes are now linked in the table and nodes. This page still only orients.
  • The hub agent-systems path now matches this map. Read the core methods first (CoT → … → Generative Agents), then open 2025–26 work as needed. This remains an orientation guide, not a fourth path type.
  • It does not back-fill later numbers into classics. Evidence, author claims, and Bloss0m judgment stay in the individual notes.

If the reading method itself is still unfamiliar, pair this map with Efficient Academic Paper Reading: The Three-Pass Approach. If you want product architecture rather than a paper family, start from the AI Agent guide.

How to use this guide

  • Entering from the paper-reading hub: the three PATHS remain; if you need the ReAct family map, stop here and follow a link.
  • Entering from a classic note: if the article links to a “reading map,” it means this page.
  • Traditional Chinese edition: use the language toggle on this page.

References

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