atlas-abstract

name	atlas-abstract
description	Phase A (Abstract) — AgentFold compression of the Locate trajectory into a ≤2000-token working-memory summary plus a Memex excerpt store. Runs in a clean-context subagent to prevent trajectory contamination. Mechanically validates that every FINDING-XXX, GAP-XXX, and ESCALATION_TRIGGER is preserved. Use after findings.md is complete and before synthesis. Triggered automatically at phase boundary, or at ≥60% context-used telemetry threshold.
allowed-tools	memex_read view_file
metadata	{"methodology":"ATLAS","phase":"A"}

SKILL: Abstract — AgentFold & Memex (Phase A)

When to use

Load when: findings.md is complete and you are about to Synthesize.

Unload when: the fold summary has passed mechanical validation and Phase S has begun.

---

Contract

Field	Value
LLM calls permitted	Yes — this phase is summarization. But see the clean-context rule below.
Tool budget	≤ 5% of mission max_tool_calls
Output	(1) a ≤2000-token fold summary in working memory; (2) a persisted Memex index

---

Why this phase exists

Long-horizon agents fail predictably when the Locate trajectory balloons beyond the attention budget. Step-wise summarization loses critical constraints; fixed truncation destroys intermediate reasoning; no summarization at all courts context rot.

AgentFold is the alternative: treat Locate as a branch that you explicitly return from. The return folds the branch into a self-authored summary whose contract is mechanically checked. The Memex holds the raw evidence, so the fold can be lossy without being destructive.

---

The clean-context rule

The fold is performed by a prompt that has seen:

• mission.md
• map.md
• findings.md

And nothing else. Specifically, no Locate transcript, no tool logs, no intermediate reasoning. Why: trajectory contamination. If the fold prompt remembers the path it took, it will preserve path-relevant details at the expense of mission-relevant details. The fold is for the mission, not the journey.

Implementation: spawn an ephemeral subagent whose only inputs are the three artifacts above and whose only output is the fold summary. Your current (parent) context keeps the returned summary; discard its working state.

---

Fold contract

The summary MUST preserve, in this order:

1. Mission header

MISSION-ID: <id>
DECISION_TARGET: <verbatim from mission.md>
SCOPE: <verbatim globs>
STATUS: completed | partial | blocked

2. Decision-ready answer

A ≤200-token prose answer to DECISION_TARGET, with inline FINDING-XXX references after each factual clause. Example:

RecordVote#call is the sole writer to cast_vote_records [FINDING-017]. It delegates authorization to VotingAuthorizer#authorize_ballot [FINDING-017]. No Sidekiq path exists [FINDING-021, GAP-003].

3. Findings index

A flat list. No claim text repeated — just IDs, tiers, and anchors.

FINDING-017 | H | app/flows/vote_casting/record_vote.rb:42-78
FINDING-017 | H | app/policies/voting_authorizer.rb:12-40
FINDING-021 | M | app/flows/vote_casting/**  (ruled_out)
...

4. Open questions / gaps

Every GAP-XXX from findings, verbatim ID and one-line status.

5. Escalation log

Every ESCALATION_TRIGGER that fired during Locate, with timestamp and resolution. (Especially important for election-critical or security-sensitive missions where triggers map to hard gates.)

---

What MAY be dropped

• Intermediate tool outputs (they're in Memex if needed).
• Failed probes that produced no finding (the ones that led to ruled_out notes are preserved via their finding).
• Narrative reasoning ("I first thought X, but then realized Y"). Downstream agents want conclusions, not process.
• Duplicate anchors across findings — listed once in the index, referenced from the answer prose.

---

Mechanical validation

Before accepting the fold, run these checks (regex-grade, deterministic):

assert every FINDING-XXX from findings.md appears in the fold index.
assert every GAP-XXX from findings.md appears in §4.
assert every ESCALATION_TRIGGER from mission.md §ESCALATION_TRIGGERS
       that fired during Locate appears in §5.
assert §2 (decision-ready answer) ≤ 200 tokens.
assert total fold ≤ 2000 tokens.
assert every sentence in §2 is followed by at least one FINDING-XXX reference.

If any check fails, the mission was under-scoped — do not retry the fold with a different prompt. Halt and escalate to human or spawn a follow-up mission.

---

Memex hygiene

What goes in

• Every raw excerpt referenced by a FINDING.
• Key intermediate queries (e.g., the symbol-probe result graph for CastVoteRecord) — byte-exact, not summarized.
• The raw findings.md (for audit).

Keying

Content-addressable, SHA-256 over the raw bytes. Example:

memex://excerpt/7f31ab...

Retrieval contract

memex.read(ref) returns bytes identical to what was written. No transformation, no summarization at read time. This is what lets downstream agents re-inject exact syntax into their context if needed.

What does NOT go in

• LLM-authored summaries (those belong in working memory).
• Tool transcripts (unless you deliberately want audit trail — expensive).
• User PII or secrets scraped during exploration. Memex is per-mission; assume any content could be surfaced to downstream agents.

---

Telemetry

Record the fold ratio:

fold_ratio = tokens(fold_summary) / tokens(locate_trajectory)

Target: ≤ 0.1 (≥90% compression). The AgentFold literature shows this is achievable and that violating it usually means the Locate phase collected too much. Feedback signal: if you repeatedly hit fold_ratio > 0.2 across missions, revisit your Locate skill — you're probably reading too much.

---

Exit gate

• Clean-context fold produced by an ephemeral subagent.
• All five required sections present.
• Mechanical validation passed.
• Memex populated and all excerpt_refs resolve.
• Parent context now holds only the fold summary + Memex index, not the Locate trajectory.
• fold_ratio recorded in telemetry.