Mcp2cli – One CLI for every API, 96-99% fewer tokens than native MCP

Every MCP server injects its full tool schemas into context on every turn — 30 tools costs ~3,600 tokens/turn whether the model uses them or not. Over 25 turns with 120 tools, that's 362,000 tokens just for schemas.mcp2cli turns any MCP server or OpenAPI spec into a CLI at runtime. The LLM discovers tools on demand: mcp2cli --mcp https://mcp.example.com/sse --list # ~16 tokens/tool mcp2cli --mcp https://mcp.example.com/sse create-task --help # ~120 tokens, once mcp2cli --mcp https://mcp.example.com/sse create-task --title "Fix bug" No codegen, no rebuild when the server changes. Works with any LLM — it's just a CLI the model shells out to. Also handles OpenAPI specs (JSON/YAML, local or remote) with the same interface.Token savings are real, measured with cl100k_base: 96% for 30 tools over 15 turns, 99% for 120 tools over 25 turns.It also ships as an installable skill for AI coding agents (Claude Code, Cursor, Codex): `npx skills add knowsuchagency/mcp2cli --skill mcp2cli`Inspired by Kagan Yilmaz's CLI vs MCP analysis and CLIHub.https://github.com/knowsuchagency/mcp2cli

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FL score

77

out of 100

Verdict

BUILD

high confidence

Competition

10

competitors found, emerging market, funded players

Trend

No signal yet

A CLI tool that significantly reduces LLM token consumption by dynamically loading API tool schemas on demand, specifically for agentic workflows.

The pain

LLM agents waste massive amounts of tokens (and thus money and latency) by injecting full API tool schemas into context on every turn, especially with large tool catalogs. Models also struggle with tool selection from noisy, large contexts.

The gap

Current solutions either compress general prompts or manage API usage at a higher level, but none directly address the 'full tool schema injection' problem by replacing it with a dynamic, on-demand CLI discovery mechanism. This creates a specific whitespace for token-efficient tool calling.

Build angle

Develop a robust 'mcp2cli' that converts any OpenAPI/MCP spec into a CLI interface, allowing LLMs to discover and use tools on demand, thereby eliminating static full schema injection from the prompt context.

Strengths

  • Addresses a specific, quantifiable, and severe pain point (token waste) in a rapidly growing market (LLM agents).
  • Offers a highly specific, novel solution (CLI-based dynamic tool discovery) that provides significant, measured token savings (96-99%).
  • The value proposition is clear and directly tackles user frustrations regarding cost and latency.
  • The problem will only become more critical as LLM agents and tool usage scale.

Risks

  • Building a universally robust and compatible CLI for all OpenAPI/MCP specs is technically challenging for a solo builder.
  • As an open-source project, establishing a clear and sustainable monetization strategy for a solo builder is a risk.
  • Competition from broader LLM optimization platforms (some funded) could make differentiation difficult in the long run.
  • The friction of adopting a new tool-calling paradigm and ensuring LLM reliability with CLI output needs careful management.

Next steps

  1. Conduct in-depth user interviews with LLM agent developers and platform engineers to confirm specific integration challenges and willingness to pay for a hosted/premium version.
  2. Develop a clear pricing model for enterprise features (e.g., advanced monitoring, managed service, enhanced security) or premium support around the open-source core.
  3. Focus MVP on a specific, popular subset of OpenAPI/MCP configurations to reduce initial build complexity and get early validation.
  4. Actively engage with AI developer communities on GitHub, Reddit, and Discord to gather feedback and build a user base for validation.

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