dsh-reliability-guards

Guardrails for small local models in DeepSeek Harness (DSH). Small models (7-35B on Ollama or similar) tend to claim success after a failed command, say they checked something without calling a tool, invent DOIs, or cut an answer in the middle. This plugin catches those cases before the user reads the answer and lets the model correct itself.

Maintenance: best-effort. Issues may go unanswered; forks are welcome.

What it does

When the turn is about to close, plain deterministic rules compare the final answer with what the tools really returned. On a finding the model receives one steering notice in the same turn (at most 2 per turn, one per code) and rewrites its answer. What is still wrong at the end stays visible under the answer.

Code	Detected when
falseSuccess	the answer claims success, but a tool call failed (error, or shell [exit code: N]) and was never made up for
actionWithoutTool	"I checked / I ran ..." with zero tool calls in the turn
announcedOnly	an action is announced ("let me check:") and nothing is called
deniedCapability	"I can't access ..." while a fitting tool is in the request
unverifiedDoi	a DOI in the answer appears in no tool result; the harness checks OpenAlex then Crossref and only an unknown DOI triggers the notice (a network error never counts as invented)
foreignScript	CJK characters the user did not write
markupLeak	a tool call written as text (<tool_call>, <function=...>, </think>)
cutAnswer	the answer ends mid-sentence or with an unclosed code block
emoji (off by default)	emojis the user did not write
frenchSpelling (off by default)	misspelled words, checked offline with enchant-2

Rules are bilingual (English and French phrasing).

Before a tool runs

• Approval card for destructive shell commands (rm, mv, git reset --hard, git push --force, dd, > onto an existing file, cp onto an existing file, ...) and for write over an existing file. Creating new files never asks.
• Backups into /tmp are refused with the reason (the folder is emptied between commands).
• /explain read-only mode: only an allow-list of tools (reads, searches, proposals) runs; everything else is refused, including tools added later. Type /explain off to leave it. Install the skill: cp -r skills/explain ~/.dsh/skills/ (or into your $DSH_HOME/skills).

Skills survive summaries: when an automatic summary hides the instructions of a skill the user invoked (/word, ...), they are re-sent.

The Web UI shows, under each turn with a finding, what was seen and whether the model corrected it. English and French UI.

Install

dsh plugin --profile web add dsh-reliability-guards
# or straight from GitHub:
dsh plugin --profile web add github:MathieuPortmann/dsh-reliability-guards

Restart the profile afterwards. Requires Node ^22.19.0 || >=24 and DSH >=0.2.0-rc.2 <0.3.0 (see Compatibility).

Configuration

Row reliability-guards in your profile's cordis.patch.yml. Every guard has an on/off switch: falseSuccess, actionWithoutTool, announcedOnly, deniedCapability, unverifiedDoi, cutAnswer, foreignScript, emoji, frenchSpelling, destructiveAsk, tmpBackupDeny, explainMode, keepInvokedSkills.

Key	Default	Meaning
maxNudgesPerTurn	2	steering notices per turn
doiTimeoutMs	15000	timeout of each DOI existence check
spellAllow	[]	extra words the spell check accepts
explainAllow	[]	extra tools allowed in /explain
llmBodyTimeoutMinutes	0	raise the HTTP body timeout for slow local models (0 = Node default, 5 min)

Compatibility

Component	Supported
Node.js	^22.19.0 || >=24.0.0 (engines.node)
DSH	>=0.2.0-rc.2 <0.3.0; declared as peerDependencies on @deepseek-ai/dsh-llm and @deepseek-ai/dsh-skill, the only DSH packages the plugin imports
Platform	Linux (tested); the plugin itself is pure JavaScript with no native addon

Tested with DSH 0.2.0-rc.2 on Node 22.23 (see Verification).

Permissions and external services

Everything the plugin can touch, and what happens when it fails:

Capability	Where	Used for	If it fails
Files (read only)	index.js (statSync)	checks whether the target of > / cp / mv already exists, so only an overwrite asks for approval	treated as "does not exist": no approval card
Files (write)	none	the plugin writes nothing; its state lives in the DSH session log	n/a
Network	lib/doi.js (fetch)	existence check of a DOI that appears in an answer but in no tool result, against api.openalex.org then api.crossref.org; nothing else is sent	a network error or timeout (doiTimeoutMs) never counts as an invented DOI
Commands	lib/spell.js (execFile)	enchant-2 -d <dict> -l with the answer's words on stdin; only when the frenchSpelling guard is switched on (off by default); no shell is involved and the arguments are fixed	program or dictionary missing, timeout (5 s): the check is skipped
Dynamic module loading	index.js (importFromDsh)	loads zod, @deepseek-ai/dsh-llm, @deepseek-ai/schemastery, @deepseek-ai/dsh-skill and, optionally, undici from the DSH installation that is running the plugin (a synchronous require of an ES module fails on Node 22). Nothing is downloaded and no code is evaluated from text (eval / new Function are not used)	undici is optional; the others are required and the plugin fails to load without them
Process-wide HTTP dispatcher	index.js	only when llmBodyTimeoutMinutes > 0 (default 0 = untouched): raises the body timeout of the global fetch for slow local models	n/a (opt-in)

The plugin also blocks actions: it asks for approval before destructive shell commands, refuses backups into /tmp, and in /explain mode refuses every tool outside an allow-list. It adds no tool of its own and runs no command on behalf of the model.

Verification

Checked on a disposable profile (DSH_HOME pointing at a temporary folder, profile cloned with dsh <name> --from-default-profile web, so the real profile is never touched):

npm pack
dsh plugin --profile t add file:$PWD/dsh-reliability-guards-0.1.0.tgz   # install
dsh --profile t --no-open --port 3095                                    # start: plugin loads, no error
dsh plugin --profile t remove dsh-reliability-guards                      # uninstall

npm test runs 33 standalone tests (rules, patterns, DOI extraction, spell check parsing, kept skills, load test of the real module) with no DSH installation needed except the load test, which skips when DSH is absent.

Develop

npm test

See SPEC.md for the rules.

License

MIT