docs(adr): rewrite ADR-0027 to match what the branch does and what is verified
The first draft claimed omitting allowed-tools grants spawning and that the list was a restriction. The repo's own sources describe the field as pre-approval, and the code now keeps the list. Rewrite the ADR to say the #116 defect was step text disclaiming spawning, that per-target behaviour for an unlisted tool is unverified, that the spawn tool is left out because its name is sourced for Claude Code only, and that the orchestrator-writes mitigation is prose, with the unmitigated security cost recorded. Rename to fit the new decision. Refs #116 Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01EGHFJextYtVQseaHPDDhxB
This commit is contained in:
@@ -1,48 +0,0 @@
|
|||||||
# A skill's body and its `allowed-tools` must agree — a spawning step needs a spawn tool or no list
|
|
||||||
|
|
||||||
**Status:** Accepted (2026-09-21)
|
|
||||||
|
|
||||||
`plugins/bin/.apm/skills/research/SKILL.md` once told the agent to "spawn one subagent per URL"
|
|
||||||
while its `allowed-tools` granted nothing that spawns. `WebFetch` was granted, so it never
|
|
||||||
hard-failed: it degraded to serial fetches in the orchestrator's own context, and the "in
|
|
||||||
parallel" wording, the page cap and the "subagents summarise, orchestrator writes" gotcha all
|
|
||||||
quietly stopped meaning anything. The #99 retrofit rewrote steps 4 and 5 as honest serial reads
|
|
||||||
with a real page cap and per-page reduction to notes (#116).
|
|
||||||
|
|
||||||
The defect was a **mismatch between what the body instructs and what `allowed-tools` permits**. It
|
|
||||||
was not that a skill spawned subagents. Three skills spawn today and work: `write-docs` (Reader
|
|
||||||
Testing sub-agent), `improve-codebase-architecture` (`Explore`, and 3+ parallel sub-agents in
|
|
||||||
`references/interface-design.md`) and `forge` (fork and clean-context subagents). None declares
|
|
||||||
`allowed-tools`, so all inherit every tool, spawning included. `research` was the only one that
|
|
||||||
both restricted the list and instructed spawning.
|
|
||||||
|
|
||||||
**Decision: a skill may instruct spawning subagents, provided its `allowed-tools` agrees with its
|
|
||||||
body.** Either:
|
|
||||||
|
|
||||||
- omit `allowed-tools`, so the skill inherits every tool on every target; or
|
|
||||||
- list the spawn tool — only once its per-target name is known, since `allowed-tools` is a flat list
|
|
||||||
and `claude`, `copilot` and `codex` name it differently.
|
|
||||||
|
|
||||||
A step that needs a tool the list does not grant must be rewritten as a step that does not need it.
|
|
||||||
That is what the #99 retrofit did to `research`, and it stays correct until one of the two options
|
|
||||||
above is taken.
|
|
||||||
|
|
||||||
Fan-out is not confined to agents. `CONTEXT.md` says a plugin-scope agent *delegates to skills*
|
|
||||||
because it cannot disclose to itself; it does not say skills may not delegate.
|
|
||||||
|
|
||||||
## Consequence for `research`
|
|
||||||
|
|
||||||
Its fan-out is restored, and `allowed-tools` is dropped to do it (version 1.0.1 → 1.1.0). That is
|
|
||||||
the first of the two options above; the second is unavailable until the per-target spawn tool names
|
|
||||||
are known.
|
|
||||||
|
|
||||||
The cost is stated rather than hidden: `research` fetches arbitrary web pages, and inheriting every
|
|
||||||
tool widens what an injected page could reach for. Two things bound it. The subagents only read and
|
|
||||||
summarise, and the orchestrator alone writes files, so the write surface is unchanged in intent. And
|
|
||||||
the least-privilege list was never enforceable across targets anyway, since it could not name a
|
|
||||||
spawn tool. If a per-target form of `allowed-tools` appears, restore a list that includes the spawn
|
|
||||||
tool.
|
|
||||||
|
|
||||||
Rejected: banning spawning in skills (contradicted by three working skills, and unsupported by
|
|
||||||
`CONTEXT.md`), and guessing a per-target spawn tool name in `allowed-tools` (no per-target form
|
|
||||||
exists, and a wrong guess reproduces the defect silently).
|
|
||||||
@@ -0,0 +1,46 @@
|
|||||||
|
# `research` gets its fan-out back and keeps its tool list; a body must not disclaim spawning
|
||||||
|
|
||||||
|
**Status:** Accepted (2026-09-21)
|
||||||
|
|
||||||
|
`plugins/bin/.apm/skills/research/SKILL.md` once told the agent to "spawn one subagent per URL"
|
||||||
|
while its `allowed-tools` listed nothing that spawns. `WebFetch` was listed, so nothing hard-failed:
|
||||||
|
the skill degraded to serial fetches in the orchestrator's own context, and the "in parallel"
|
||||||
|
wording, the page cap and the "subagents summarise, orchestrator writes" gotcha quietly stopped
|
||||||
|
meaning anything. The #99 retrofit rewrote steps 4 and 5 as serial reads and said in the text that
|
||||||
|
no subagent tool was granted (#116).
|
||||||
|
|
||||||
|
**What #116 did not establish.** It read the missing tool as the cause. The repo's own sources
|
||||||
|
describe `allowed-tools` as pre-approval, not restriction: `skill-author/references/create.md:113`
|
||||||
|
("space-separated pre-approved tools; reduces permission prompts"), the agentskills.io
|
||||||
|
specification, and the Copilot plugin docs. On that reading an unlisted spawn tool would prompt, not
|
||||||
|
fail. What Claude Code, Copilot and Codex actually do with an unlisted tool is **not verified
|
||||||
|
here**, and neither is whether omitting the field grants anything. What is documented is that the
|
||||||
|
serial behaviour followed the step text, which told the agent to go serial.
|
||||||
|
|
||||||
|
**Decision.** `research` keeps its `allowed-tools` list and gets its parallel fan-out back in steps
|
||||||
|
4 and 5, with the "subagents read and summarise; the orchestrator writes every file" gotcha
|
||||||
|
restored (version 1.0.1 → 1.1.0). A skill body that instructs spawning must not be paired with text
|
||||||
|
saying spawning is unavailable.
|
||||||
|
|
||||||
|
The spawn tool is **not** added to the list. Its name is sourced for Claude Code (`Agent`) only; the
|
||||||
|
Copilot and Codex names are not known. On Claude Code, spawns therefore prompt instead of being
|
||||||
|
pre-approved. Add the tool once its name is sourced for each target.
|
||||||
|
|
||||||
|
**Corpus facts, with limits.** `write-docs`, `improve-codebase-architecture` and `forge` all omit
|
||||||
|
`allowed-tools` and instruct spawning subagents — `forge` from `references/author-routes.md` and
|
||||||
|
`references/version-bump.md`, not from its `SKILL.md`. That shows they spawn, not that a run
|
||||||
|
succeeded. `skill-author/SKILL.md:24` forbids spawning a subagent to recheck one's own work, which
|
||||||
|
is a different question and unaffected here. `CONTEXT.md` says a plugin-scope agent delegates to
|
||||||
|
skills because it cannot disclose to itself; nothing there bans a skill from delegating.
|
||||||
|
|
||||||
|
**The security cost is real and not mitigated.** "The orchestrator alone writes files" is prose,
|
||||||
|
not enforcement. The subagents read untrusted web pages, and nothing restricts what tools they
|
||||||
|
hold. Not done, by decision: an instruction to treat fetched page content as data, a cap on the
|
||||||
|
number of subagents (user-supplied URLs are uncapped, and the step 5 page cap bounds less once
|
||||||
|
reads run in parallel), and read-only subagents. `docs/research/ai-coding-factory/
|
||||||
|
ai-coding-factory-principles.md:53` recommends applying `allowed-tools` restrictions, which is why
|
||||||
|
the list was kept.
|
||||||
|
|
||||||
|
Rejected: dropping `allowed-tools` on the premise that it blocked spawning (unsupported by the
|
||||||
|
repo's own sources, and it widens the tool surface for nothing), and banning spawning in skills
|
||||||
|
(three skills instruct it, and `CONTEXT.md` does not forbid it).
|
||||||
Reference in New Issue
Block a user