dsh-office-toolsDeepSeek Harness plugin

dsh-office-tools

Eight model-facing Office file tools for DeepSeek Harness, running entirely in the plugin host half.

Install: dsh plugin --profile web add github:kw78/dsh-office-tools

Tool	Purpose	Library
word_create	Create .docx (title, paragraphs, bullets, one table)	docx
word_read	Extract text from .docx; format: "markdown" renders headings, lists, and tables structurally	jszip (in-house extractor)
word_update	Append paragraphs, bullets, and/or a table to an existing .docx	docx + jszip
excel_create	Create a multi-sheet .xlsx from scalar cell grids	SheetJS (xlsx)
excel_read	Read one or all sheets as scalar rows; formulas return cached values or '=…' strings	SheetJS
excel_update	Replace/create whole sheets, or write cells by A1 address	SheetJS
ppt_create	Create a 16:9 .pptx (title slide, titles, paragraphs, bullets, notes, PNG/JPG/GIF images)	pptxgenjs
ppt_read	Extract per-slide paragraphs, tables, speaker notes, image counts, and image alt texts	jszip

String cells starting with = are written as real Excel formulas (Excel computes them on open).

Demo

One prompt, a quarterly-report trio — Word with a metrics table, Excel with =SUM/variance formulas, PowerPoint with speaker notes:

The prompt behind that session:

Generate the Q3 quarterly-report trio: report.docx (title, two summary paragraphs, three highlights, a metrics table), budget.xlsx (a Budget sheet with =SUM totals and plan-vs-actual variance formulas, plus a Summary sheet), and deck.pptx (title slide + three content slides with speaker notes).

The model turns it into word_create → excel_create → ppt_create (reads come back through word_read / excel_read / ppt_read; freshly written formulas read back as '=…' strings until Excel caches values). The whole flow is pinned by tests/demo-trio.spec.ts, so the demo cannot drift from the tools. The file sizes in the image come from a real run of that test scenario.

Harness integration

The plugin follows the standard DSH host-plugin contract:

• It exports name / inject / apply / Config; inject = ['tools'] is its only runtime service dependency (@deepseek-ai/dsh-tools).
• apply(ctx) wraps every ctx.tools.register(defineTool({...})) in ctx.effect(...) so Cordis disposes the registrations with the plugin fiber.
• defineTool declares model-visible parameters, a validated canonical output.schema, and a pure output.render text projection.
• execute(args, exec) resolves every path against exec.agent.session.header.cwd; relative paths stay in the session workspace and absolute paths are accepted only when still inside it. A realpath check on the nearest existing ancestor closes the symlink escape hatch.
• Image files must live inside the session workspace (.png/.jpg/.jpeg/.gif, 20 MiB each); explicit inch coordinates x/y/w/h are supported, or omit them for automatic placement below the text.
• Writes go through a same-directory temp file + rename; overwrite defaults to false.

Build

bash
pnpm install
pnpm run check   # typecheck + tests + build

Artifacts: lib/index.js (ESM host bundle of this plugin's own code plus schemastery — 90 kB; the Office libraries are regular runtime dependencies resolved from the profile's node_modules) and lib/types/**/*.d.ts. @deepseek-ai/* and cordis stay external.

Install

bash
# npm (recommended)
dsh plugin --profile web add dsh-office-tools

# GitHub source
dsh plugin --profile web add github:kw78/dsh-office-tools

# local checkout
dsh plugin --profile web add /path/to/dsh-office-tools

Restart the DSH server after installation. The eight tools appear in the next prompt assembly. Note: since 0.6.0 the Office libraries are runtime dependencies, so installation fetches them (npm, plus cdn.sheetjs.com for SheetJS — ~15–20 MB); the plugin package itself is ~32 kB.

Configuration

The plugin declares a schemastery Config the Loader validates at load time. One option exists today:

Option	Type	Default	Effect
enablePptTools	boolean	true	Register ppt_create / ppt_read. Set to false to load this plugin for Word/Excel only.

enablePptTools: false exists for coexistence: dedicated presentation plugins such as dsh-ppt also register a ppt_create, and DSH refuses duplicate tool names at startup (tool "ppt_create" is already registered). Disable the PPT pair here and let the dedicated plugin own presentations:

yaml
# profile cordis.patch.yml
- insert:
    - id: dsh-office-tools
      config:
        enablePptTools: false

Community indexes

• Registration blocks for awesome-dsh-plugin / dsh-market are in docs/hub-registration.md.
• Recommended repository topics: dsh, dsh-plugin, deepseek-harness, office.

Safety

• All file access is confined to the calling agent's session workspace.
• Reads are capped at 50 MiB compressed; before anything is inflated, the archive's own declared sizes are checked against budgets (256 MiB per entry, 512 MiB per archive, 100 000 entries), so zip bombs are refused rather than decompressed. XML parts carrying DOCTYPE/ENTITY declarations are refused outright.
• Text/cell results are bounded and mark truncated.
• Creates/updates are bounded by row and cell limits and refuse overwrites by default.
• No LibreOffice/PowerPoint/Word subprocess is spawned; formats are generated and parsed with pure-JS libraries.
• SheetJS is pinned to the 0.20.3 tarball from the official CDN (https://cdn.sheetjs.com): npm stopped at 0.18.5, which carries CVE-2023-30533 (prototype pollution) and CVE-2024-22363 (ReDoS); fixed releases are only distributed through the official CDN. Since 0.6.0 it is a URL-pinned runtime dependency — installs download exactly this tarball from the CDN, never the vulnerable npm release.
• Roadmap: docs/ROADMAP.md.