ctx · 文脉 · the substrate

Agents that
change behavior. On the record.

usectx.com hosts long-lived agents alongside the resources they need — Postgres, blob, queues, mail — and an event log that proves they change behavior. Every durable change is a typed tool call with a reason. op0 is the reference app — a creative studio you coach by speaking, where the agent shapes its own workspace per user.

workflow lane pass · prod: 100%
fastest run · iad1 colocated: 17s
vs local dev · region pinned: −47%

Open op0 studio Read the audit trail github · arthtyagi/ctx

canvas.flow

One audited surface.Three actions. Two outputs.

01 · owner.dm

owner.dm · poll 7

reverse what I said

release notes in #announcements ARE important, especially breaking changes.

owner.dm · poll 12

create an agent

that listens to my voice memos and surfaces structured snippets — speakers, beats, key sections.

02 · ctx.reasoner · Opus 4.7

rule storestate/rules.json

rule_001Suppress gm/gn messages from the digest.
rule_002Always surface @-mentions of owner as priority one.
rule_003In #help, suppress install Qs already answered by docs_bot.
rule_004Flag any message from @daisy as priority — she's on the team.
rule_006Surface release notes and breaking changes from #announcements.replaces rule_005
rule_005Suppress messages from #announcements, mostly noise.retired @ poll 7 · belief revision

tool: instructions(upsert | retire | create_agent, payload, reason)

03 · outputs

agent.message · ctx-renderer · Haiku 4.5

Digest — Poll 7

m032 [#announcements] @daisy: shipping v0.5.0-beta.1 — breaking middleware signature changes, migration guide required.

surfaced via rule_006 · rule_005 retired same poll

agent_spec · spec_001

voice-memo-summarizer

Summarize voice memos into structured snippets — speakers, beats, key sections.

tool_refs: [audio_analyze]

session.events

Eight events. One audit trail.

Two coaching DMs, one belief revision, an eval gate, and a new agent — all recorded as events.list() entries on the underlying Managed Agents session. Mirrored to a memstore as immutable memory_versions.

owner.dmpoll 1
“less gm/gn in the digest please”
instructions.upsertpoll 1
Suppress gm/gn messages from the digest.
reason: Owner said 'less gm/gn in the digest please' — explicit request to dial down gm/gn chatter.
+ rule_001
owner.dmpoll 7
“wait actually — release notes in #announcements ARE important, especially breaking changes. reverse what I said about dialing it back.”
instructions.retirepoll 7
Suppress messages from #announcements, mostly noise.
reason: Owner said 'reverse what I said about dialing it back' — explicit retraction of the #announcements suppression rule.
✕ rule_005
instructions.upsertpoll 7
Surface release notes and breaking changes from #announcements as important.
reason: Owner said 'release notes in #announcements ARE important, especially breaking changes.'
rule_005 → rule_006
eval.resultpoll 10
digest relevance 86.0% → 93.6%, critical recall 100%, 1 retire event
86.0% → 93.6%
owner.dmpoll 12
“create an agent that listens to my voice memos and surfaces structured snippets — speakers, beats, key sections”
instructions.create_agentpoll 12
voice-memo-summarizer — Summarize voice memos into structured snippets — speakers, beats, key sections.
reason: Owner asked: 'create an agent that listens to my voice memos and surfaces structured snippets — speakers, beats, key sections'.
+ spec_001 · tool_refs:[audio_analyze]

substrate · Anthropic Managed Agents

Four concepts.Four chat-native surfaces.

Managed Agents is built around four primitives. ctx makes each one legible — Agent, Environment, Session, and Events map to the agents you coach, the sandbox they run in, the per-task trace, and the audit log of every behavior change.

AgentPersistent identity with progressive skill disclosure per turn.: Three: ctx-reasoner (Opus 4.7) wires the instructions tool; ctx-narrator (Opus 4.7) re-reads the event log for /observability; score-renderer (Haiku 4.5) calls audio_analyze + the music provider router and emits a sketch.
EnvironmentSandboxed compute, per session.: When an image references a URL or the agent needs to fetch a reference track, the call goes from inside the session container. Every tool call is bounded to its session.
SessionOne per drop, same agents across drops.: Each painting you drop opens a session referencing the persistent agents. Server-persisted event history travels with the session; the memstore mounts read-only when context demands it.
EventsSource of truth for audit.: /observability queries events.list() across all your sessions. Memory versions add an immutable artifact trail attributable to each session_id. No shadow logging, no parallel write path.

Agents thatchange behavior. On the record.

Agents that
change behavior. On the record.