Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add instructions/sbroenne/mcp-server-excel/copilot-instructionsgit clone --depth 1 https://github.com/sbroenne/mcp-server-excelWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/sbroenne/mcp-server-excel/copilot-instructions)<a href="https://agentmods.dev/instructions/sbroenne/mcp-server-excel/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/sbroenne/mcp-server-excel/copilot-instructions.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.01206 | $0.01206 |
| Opus 5 | $0.00603 | $0.00603 |
| Sonnet 5 | $0.00241 | $0.00241 |
| Haiku 4.5 | $0.00121 | $0.00121 |
Grade A, and why
mcp-server-excel copilot-instructions.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 109 lines — stays where its author put it; the contents beside it link to each section on GitHub.
GitHub Copilot Instructions - ExcelMcp
ExcelMcp is a Windows-only .NET 10 solution that automates desktop Excel through
COM. It has two equal user entry points: the MCP Server and excelcli. A feature
is incomplete if those surfaces differ in behavior, validation, defaults, or
documentation.
Repository map
src/ExcelMcp.ComInterop: STA execution, COM lifetime, sessions, shutdownsrc/ExcelMcp.Core: Excel operations and result modelssrc/ExcelMcp.Service: command dispatch used by both entry pointssrc/ExcelMcp.CLI: CLI client and daemon transportsrc/ExcelMcp.McpServer: MCP tools and in-process service bridgesrc/ExcelMcp.Generators*: generated CLI, service, and MCP surfacestests: xUnit projects; most Core behavior tests require desktop Excelskills/shared: source of truth for shared CLI/MCP agent guidancegh-pages: MkDocs site built from canonical repository documentation
Environment
- Use Windows and PowerShell. The pinned SDK is in
global.json. - Microsoft Excel is required for COM integration tests and local end-to-end smoke tests. GitHub-hosted runners can build the solution but do not have Excel; never report Excel-dependent tests as passing there.
.github/workflows/copilot-setup-steps.ymlprepares cloud-agent dependencies.
Working rules
- Read only the path-specific files under
.github/instructionsthat match the files being changed. Those files contain the detailed implementation rules. - Diagnose behavior before editing. For a bug or feature, add a focused regression/integration test first, observe the expected failure, implement the fix, and rerun that test. Pure documentation and configuration changes do not need a synthetic test.
- Search for the same contract or generated pattern across Core, Service, CLI, MCP, tests, skills, and docs. Update every affected surface.
- Preserve unrelated worktree changes. Do not create temporary planning or summary files in the repository.
- Prefer existing helpers and generated surfaces. Do not duplicate dispatch, validation, serialization, COM cleanup, or documentation-count logic.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 4d ago First seen · 109 lines · 1,206 tokens per session scan A fa3034b4b6f0
mcp-server-excel copilot-instructions.md is an instructions file published in the GitHub repository sbroenne/mcp-server-excel (653 stars, last pushed today), licensed MIT. It adds 1,206 tokens to every session, about $0.0060 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
mcp-server-powerpoint copilot-instructions.md
Copilot instructions for sbroenne/mcp-server-powerpoint, covering project instructions — powerpointmcp, critical files (read these first), sister projects, what is powerpointmcp? and session model (mcp server).
mcp-server-powerpoint architecture-patterns.instructions.md
Instructions for sbroenne/mcp-server-powerpoint, covering architecture patterns, .net class design (mandatory), layered architecture (critical), command pattern and structure (per domain).
mcp-server-powerpoint critical-rules.instructions.md
Instructions for sbroenne/mcp-server-powerpoint, covering critical rules - must follow, rule 1: success/errormessage invariant, rule 1b: no exception suppression in core, rule 30: real-com integration tests only, strict tdd and rule: 1-based indexing everywhere.
mcp-server-powerpoint mcp-server-guide.instructions.md
Instructions for sbroenne/mcp-server-powerpoint, covering mcp server development guide, llm-facing content rules, two kinds of tools: hand-written vs. generated, implementation pattern: single hand-written dispatch tool and error handling (mandatory).
mcp-server-powerpoint testing-strategy.instructions.md
Instructions for sbroenne/mcp-server-powerpoint, covering testing strategy, strict tdd (red → green), test project layout, serialization is mandatory and trait tagging (required for surgical filtering).
mcp-server-powerpoint code-review.instructions.md
Instructions for sbroenne/mcp-server-powerpoint, covering copilot code review, interop and resource safety, contract and path completeness and protocol, tests, and user-facing surfaces.