SBCJuly 31Flashbots

From Hardware to Harness_

A harness is the agent's execution surface, and markets of agents can be read as harnesses talking to harnesses. Search makes that interface concrete: an agent moves between local files and the remote web, while queries, payments, network metadata, and the timing of tool calls determine what the market can learn about it.

speaker dmarzruntime 32 minformat talkreading time ~9 min

Watch on Youtube

tl;dr

›
The harness is an economic interface.

If agents become the main interface to markets, identity, payments, tool calls, and cooperation are not separate plumbing; together they shape who can act and what others can observe.

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Private search has more than one leak.

Encrypting a query and index can hide content, while IP address, frequency, query size, timing, and a non-private payment still correlate an agent's identity.

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Round-based privacy may fit agents better than humans.

In the observed workflow, six searches ran in parallel across two rounds, while the longer bottleneck was the agent reasoning over results before making another remote model call.

If you're new to any of this

An AI model does not act alone. A harness gives it memory, tools, permissions, payments, and the ability to call outside services. This talk zooms in on search as one of those services and asks what privacy means when an agent has sensitive intent. Encrypting a query or running a service in protected hardware can hide content, but network timing and identity may still reveal who is searching and when.[6]

›A bit more background

Agent-oriented search APIs such as Exa and Parallel show how search is becoming a callable tool inside a model's workflow. A trusted execution environment, or TEE, isolates code and data while they are in use and can provide attestation about the software being run. That can protect a query inside a search service, depending on the implementation and trust model. It does not automatically conceal network metadata, operator behavior outside the protected environment, or every component that handles the request.[6][7][8]

Private retrieval takes a different route. Systems such as TIPTOE use cryptographic protocols so a client can search semantic embeddings without revealing the query to the server in ordinary plaintext. The result protects a particular information boundary; it does not by itself hide when the client connected, where traffic came from, or how query and response sizes correlate. The Periscope prototype discussed in the talk remains transcript- and deck-attributed rather than independently verified.[4]

A mix network addresses that metadata layer by routing messages through intermediaries and mixing them with other traffic, delays, or cover messages. This makes traffic analysis harder, but it introduces latency and coordination costs. The talk's design intuition is that agents may tolerate round-based communication better than humans because search already happens in bursts and model reasoning takes time. TEE execution, private retrieval, and mixnets therefore protect different surfaces; none is a substitute for the other two.[5]

Show slides
01

The harness becomes an economic interface

I moved from the hardware side to the harness side. The harness is the agent's execution surface and what the rest of this track will focus on. It connects a model to memory, tools, credentials, payments, and the outside world. Moving from hardware to harness shifts attention from who supplies intelligence to who controls execution and the information produced along the way.

The word harness doesn't really make you think of a market. Operationally, however, it governs which context reaches a model, which tool calls it can make, which permissions accompany them, and how results return. Hardware supplies computation; the harness determines how that computation becomes an action in a market.

Zoom into the harness slide narrows the track from model supply to the agent execution surface.
slide 04The track zooms from model supply into the agent execution surface.

As I put it, agent markets can be analyzed as communication between harnesses. One configured system sends an intent or tool call to another, and the two boundaries enforce the terms. You can analyze this from a harness perspective because the transaction is carried by models plus memory, credentials, policies, and tools—not by a bare model.

“Markets of agents are basically just harnesses talking to harnesses.”

— dmarz

If agents become the main economic interface to markets, harnesses become economic interfaces too. The same model can act for different principals when its harness supplies different memories, identities, and spending authority. Conversely, a nominally decentralized market can concentrate control in a shared execution provider. Economic agency inherits the constraints of the machinery around the model.

Agents become the economic interface slide shows markets as harnesses communicating with other harnesses.
slide 06Agent markets can be analyzed as harnesses communicating with harnesses.
02

Four surfaces define the privacy boundary

I broke the harness into a four-part surface map One is identity and auth. Two is payments, including transactions in Ethereum or the blockchain and sometimes intents. The remaining surfaces are tool calls and cooperation. They overlap in practice: one tool call can authenticate an agent, spend money, and disclose information to another service at the same time. It makes market structure visible where an abstract capability becomes a concrete permission, call, or transfer.

This is a very rough mental model, meant to break it down for this section rather than impose a formal taxonomy. When an agent fails to act, gains privileged access, or leaks information, the map helps locate which surface carried the decision.

Four-box harness model lists identity and authorization, payments, tool calls, and cooperation.
slide 07Four harness surfaces cover identity, payments, tool calls, and cooperation.

Put on your market structure hat and privacy becomes part of the mechanism. There are many arguments that the ability to operate privately in the market is paramount to market efficiency. The harness must preserve that ability across each exposed surface, not merely inside the model or memory store. Search is a useful test because a tool call can itself disclose strategy. Protecting memory does not hide the remote query, while encrypting content does not hide network or payment metadata.

The practical question is whether you can do all of these agentic things with your harness and actually preserve your privacy. An agent may inspect local material, derive a query, send it over the internet, receive results, and pay a provider.

An efficient market wants privacy slide lists confidentiality and strategic-operation reasons for private agent activity.
slide 10Efficient agent markets require privacy across the full execution path.
03

Search APIs form a remote market

For this test, an agent has some type of model: it can be local or remote, it has memory, and it has tool calls. The query may summarize what the agent knows, wants, or plans next, making the request a statement of intent as well as a retrieval operation. A local file lookup and a remote web request can satisfy the same need while creating very different ownership, latency, and privacy boundaries for the harness.

That path is one area where information can be leaked. Search therefore has three relevant properties: where retrieval runs, how the provider is paid, and what the interaction reveals. Search crosses those components and reaches the open internet or a private internet.

Totally private agents diagram separates model, memory, tool calls, payments, and their local or remote placement.
slide 13The agent stack places models, memory, tools, and payments locally or remotely.

There are now search engines built for agents, which raised my first question: what makes these search engines agentic? Exa presents itself as the search engine for AI, while Parallel describes infrastructure for intelligence on the web. Both use embedding-based retrieval, but established search providers use similar techniques. Embeddings alone do not define an agent-facing market. An agent service might instead charge through an API, compress results for model consumption, or collect payment per search.

The redistribution mechanism may matter more. Humans get fed ads, and those ads pay for the search engine. It is unclear what that means to an agent; you probably don't want your agent to be fed ads inside its reasoning loop.

Comparison card quotes Exa as search for AI and Parallel as web-intelligence infrastructure, with speaker questions about agentic search.
slide 15Exa and Parallel prompt the question: what makes search agentic?
04

Local corpora change who owns retrieval

Human search returns pages and promotions to a person. An agent tool returns material that another model will reason over, so promotional content can affect downstream decisions rather than only attention. A paid API removes the ad, but payment identity and policy join the retrieval boundary. Search goes over the remote internet, and payment may expose the caller again. A lot of agent search is actually local as well, even when operators call it grep, indexing, file lookup, or retrieval.

From the harness perspective, these are still tool calls that locate information. The important distinction is that local lookup works over material already held, while public-web retrieval discloses the immediate question to a remote provider.

Assume the rest is solved slide isolates search while holding model, memory, payment, and network questions constant.
slide 16Holding the rest constant isolates search as the contested tool.

Search can be over your local data—what you've already captured—or remote data on the public web. Local retrieval changes when disclosure happens. Operators can collect likely sources ahead of time and let an agent query a private copy later. That moves work from question time to collection time and changes both latency and which observer sees the request. The operator still decides what to capture, how often to refresh it, and whether to trust the cache.

Talk to anyone running agents and they're scraping massive amounts of data. The resulting boundary is porous: an agent may search locally first and use the web only for gaps, or scrape remotely on a schedule and reuse the corpus throughout the day.

Search splits in two diagram branches into local captured data and remote public-web data.
slide 17Search branches into captured local data and the remote public web.
05

Agents can build their own search layer

The examples in the room followed this pattern. One operator learned that the U.S. Patent Office was taking all of the patents off their API and began preserving the material. Another had an agent checking Hacker News, GitHub, and a few other things every morning. Scheduled collection reduced the need for a revealing remote call at task time.

These anecdotes suggest a common stack: a collector makes remote requests in bulk, a local index stores the results, and later reasoning searches what was captured. The workflow can be faster and reveal less at query time. It does not eliminate privacy cost; it moves the cost into collection and storage, while the agent need not make those calls during every task.

Everyone is already scraping slide combines local-agent examples with a chart of archived information sources.
slide 19Scheduled scraping turns repeated remote lookups into a local corpus.

Zero-click search points in the same direction. A zero-click search is when a search interface supplies an answer before the user follows a result. I cited talk-reported figures of 58.5% of searches ending without a click in 2024 and 68% by early 2026. Those figures were not independently verified here, but the interface change is the relevant mechanism.

Once a user is not clicking on a link anymore, retrieval, synthesis, and browsing separate. My claim was that this entire portion of the market could get eaten up by local search: an agent captures likely sources, synthesizes over them, and avoids repeated public queries. The shift also disrupts the familiar advertising and referral loop.

The Zero-Click Majority slide contrasts talk-reported search figures of 68 percent in early 2026 and 58.5 percent in 2024.
slide 21The deck contrasts talk-reported zero-click figures from 2024 and 2026.
07

Encrypted answers can still leak identity

The interface suggests a private service: someone builds an index of a useful slice of the web, encrypts it, and lets agents submit protected queries. No one can actually see inside the index or understand what is inside; the server sees an encrypted blob. The deck names a related prototype, Periscope, without establishing ownership, deployment, or current status.

Retrieval quality creates a second tension. Search queries are getting longer and longer over time—by the talk's estimate, roughly two words per year—while in embedding search longer queries often retrieve worse matches. Effective agent retrieval may split one request into many small searches, multiplying the number and pattern of observable calls.

“Even if you have one of these private search engines, you can still be revealed through your metadata.”

— dmarz
Periscope architecture routes private queries through an encrypted index and returns results to an agent, as presented in the deck.
slide 26The deck's Periscope frame routes encrypted queries through a private index.

Even with encrypted retrieval, this IP can make the same ten queries every single day. A search operator may correlate the source IP, timing, count, and response size, then start to correlate that identity without reading the content. Repetition becomes a fingerprint that links nominally private calls to one agent or organization.

The lesson is that you can still be revealed through your metadata, even if you have one of these private search engines. A private harness must therefore control routing, timing, batching, and payment. It may hide the source IP or mix calls with other traffic before reaching the encrypted index, preventing content and network behavior from recombining into an identity.

Metadata Is the Remaining Leak slide shows repeated query timing and size patterns that can correlate a supposedly private agent.
slide 27Repeated timing, size, and IP patterns can correlate a private agent.
08

Round-based privacy may fit agent search

Trying to hide metadata leads to several network designs. Tor uses onion routing: you take your message and you encrypt it three times for three relays, which peel off one layer at a time. Nym-style mixnets and DC-nets differ because they are round-based protocols. A request may wait for a round rather than leave immediately. The protocol must progress through the rounds before it starts letting the message in.

That delay looks costly for interactive search, so I wanted to explore whether agents would tolerate round-based protocols for search. With Tor, you fire a request off straight away; with a round-based protocol, it may arrive midway through the round and wait.

Completed agent-search dashboard shows a timing diagram with six parallel web searches clustered into rounds and longer reasoning gaps.
slide 45Six parallel searches cluster into rounds separated by longer reasoning gaps.

I augmented my agent with tooling to record when it was using web-search tools, then gave it deep-research tasks. With access to sub-agents, it performed six web searches in parallel in roughly two rounds, thought for a while, fetched more material, and repeated the pattern. The trace was bursty and batched rather than one continuous sequence of clicks.

The tool calls were bottlenecked by the agent's ability to think and reason over responses, especially when another remote-model call followed. In that workload, agents use search differently from humans: they are tolerant of wait times and can schedule things ahead intelligently. That supports testing round-based privacy, not claiming every protocol fits every agent workload.

“Agents don’t have the same profile as humans for search, where they’re quite tolerant to wait times, and they can also schedule things ahead intelligently.”

— dmarz
Agents Tolerate Rounds slide compares round wait time with the longer model-reasoning interval between search bursts.
slide 47Round waits can fit inside the agent's longer reasoning interval.
A

Appendix

The deck's concept map belongs to the event framing, not to dmarz's first-person talk body. It connects four broad themes—AI for MEV, MEV-aware AI, agentic markets, and the infrastructure path from hardware to harness—and situates this presentation in the last branch. The map is useful orientation for readers, but its labels should not be treated as claims that dmarz developed every adjacent topic. Tina's earlier spoken introduction is likewise excluded from the first-person narrative; this appendix preserves only the slide-attributed relationship among the program themes.

Agentic MEV concept map connects AI for MEV, MEV-aware AI, agentic markets, and hardware-to-harness layers.
slide 03The event map connects MEV, agent markets, hardware, and harness layers.

Glossary & further reading

agent harness — An agent harness is the execution layer around a model. It supplies memory, tools, permissions, identity, payments, scheduling, and other controls that turn a model response into action.

trusted execution environment (TEE) — A trusted execution environment is a hardware-based, attested environment intended to protect data while computation is running. It is one approach to confidential service execution, not a complete anonymity system.[6]

private search — Private search aims to return useful matches without revealing the query, corpus, or results beyond the intended parties. Different systems protect different pieces and may still expose traffic metadata.[4]

mix network (mixnet) — A mix network relays messages through intermediaries and mixes them with delays or cover traffic to resist traffic analysis. Its round or latency profile can differ from low-latency onion routing.[5]

References

  1. [01]Flashbots at SBC 2026 — Flashbots CollectiveFlashbots’ event recap lists the Agentic MEV agenda, speakers, and recordings.
  2. [02]Plausible Pluralities — dmarzdmarz’s technical blog covers AI, biology, infrastructure, and internet systems.
  3. [03]Agentic Ethereum — ETHGlobalETHGlobal’s Agentic Ethereum hackathon focused on AI, crypto, privacy, identity, and TEEs.
  4. [04]Private Web Search with Tiptoe — IACR Cryptology ePrint ArchiveTiptoe hides web-search queries using semantic embeddings and homomorphic encryption.
  5. [05]The Loopix Anonymity System — Ania Piotrowska, Jamie Hayes, Tariq Elahi, Sebastian Meiser, and George DanezisLoopix uses cover traffic and delays to resist traffic analysis in a mix network.
  6. [06]Confidential Computing Consortium Scope — Confidential Computing ConsortiumDefinition of confidential computing using hardware-based, attested execution environments.
  7. [07]Search API Reference — ExaExa’s API reference covers search modes, requests, responses, and agent examples.
  8. [08]Search API Best Practices — ParallelParallel’s guide explains how agents should structure search queries and results.