papyrus-trace

name	papyrus-trace
description	Atomic — follow supersession chain and direct links of one need

papyrus-trace

Print the supersession chain (what this need supersedes, recursively) and direct typed links of one need. Focused variant of impact for historical walks.

Atomicity

• (a) Indivisible: one read over the chain + direct edge enumeration, read-only
• (b) Input: mem_id. Output: header + direct links + supersession chain (newest → oldest)
• (c) Objective reward: fixture with chain of length N produces N lines in chain output
• (d) Reusable: audit flows, decision history, deprecation review
• (e) No interference: read-only

Input / Output

input:
  mem_id:  starting need id
output:
  stdout:  "=== <id> — <title> ===" header with type/status/created/updated line
           "Direct links:" section (when any) grouped by link type
           "Supersession chain (newest → oldest):" section (when any), one id per line
  exit:    0 on success; non-zero if id not found

When the chain crosses into an external pharaoh workspace, a marker line is printed: (chain continues into external pharaoh: <id> — <title>).

Success criterion

Given fixture where DEC_v3 supersedes DEC_v2 supersedes DEC_v1:

papyrus trace DEC_v3

Output includes all three ids on separate lines in the supersession chain section.

Workflow

CLI:

papyrus trace <mem_id>

MCP tool memory_trace:

{"mem_id": "DEC_current"}

Composition examples

Deprecation audit:

1. papyrus-query --status deprecated lists deprecated needs
2. For each: papyrus-trace shows what replaced it

Decision history:

1. Before writing a new DEC, papyrus-trace on the related topic finds prior versions
2. New DEC uses a supersedes link to continue the chain

Change-request context:

1. Change request touches a need
2. papyrus-trace on that need shows whether it's the latest version or already superseded

See also

• papyrus-impact — broader bidirectional graph walk
• papyrus-deprecate — common producer of supersession chains
• shared/impact-analysis.md — graph semantics