Vendor intelligence for AI coding agents choosing developer tools and stacks.
BuyAPI MCP Server (io.github.TheSnakeFang/buyapi-mcp)
The BuyAPI MCP server provides vendor intelligence for AI coding agents selecting developer tools and stacks. It is associated with the “BuyAPI CLI + MCP Server” and is described as helping agents make informed infrastructure decisions when choosing components such as a database, auth provider, hosting platform, or payment system.
🛠️ Key Features
Vendor intelligence for AI coding agents
Exposes 7 tools (toolCount: 7)
Uses the BuyAPI CLI + MCP Server package (name: io.github.TheSnakeFang/buyapi-mcp)
🚀 Use Cases
Selecting a database for an agent workflow
Choosing an auth provider
Picking a hosting platform
Selecting a payment component
⚡ Developer Benefits
Supports developer tooling decisions via vendor intelligence
Provides access to multiple tools (7 total) for agent use
⚠️ Limitations
Available documentation excerpt is incomplete and does not list specific tool names or supported capabilities beyond the decision areas mentioned above.
Captured live from the server via tools/list.
vendors.resolve
First stop for category-specific vendor recommendations and vendor ID discovery. Finds BuyAPI vendor IDs for a user question; provide category when known.
Use this when the user asks which provider in a category fits their constraints. With a covered category, the response includes ranked results plus a top-3 decision matrix with fit labels, confidence, tradeoffs, cost notes, freshness, and sources. Do not use this for local coding/debugging/docs questions unless they involve choosing a software vendor or tool.
If the category is outside BuyAPI's corpus, the tool returns an explicit "not in corpus yet" result instead of inventing vendors.
Parameters2
query
string
required
The user's question or task context for relevance ranking
Follow-up tool for one known vendor. Retrieves detailed pricing, features, limits, gotchas, comparisons, and source provenance.
Call vendors.resolve first unless the user already provided a BuyAPI vendor ID like /database/supabase. Use this after a candidate is selected and the user needs claim-level pricing, limit, gotcha, or provenance details.
Returns recent reviewed BuyAPI evidence rows for a vendor, category, stack, or comparison.
Use this when the user asks why BuyAPI believes something, what sources support a recommendation, or what recent human/source/opinion/history signals exist. This is a trust and provenance follow-up, not the first recommendation tool.
Finds reviewed public stack examples related to a vendor, or recent curated stack examples.
Use this when the user asks who uses a tool, what similar builders use, or wants examples of real stack combinations. Do not use it as a generic recommendation tool.
Compares two or more already-known BuyAPI vendors for a specific workload or decision.
Use this when the candidate set is known, for head-to-head questions like "Convex vs Supabase vs Neon for a realtime SaaS" or "Stripe vs Paddle for a marketplace". If the user has not named candidates, use vendors.resolve first.
Parameters3
vendorIds
array
required
BuyAPI vendor IDs, e.g. ['/database/convex', '/database/neon']
query
string
required
The user's decision context
workload
object
optional
Explicit workload assumptions for directional cost estimates. Missing fields become assumptions, not fabricated precision.
Produces directional monthly cost estimates from BuyAPI pricing data and explicit workload inputs.
Use this only when the user asks for cost math and provides explicit workload inputs. Missing workload fields are returned as assumptions or unknowns instead of being hallucinated. Treat results as BuyAPI claim-based estimate math; verify exact billing in first-party docs, vendor CLIs, or vendor MCPs before purchase or production decisions.
Parameters3
vendorIds
array
optional
Optional vendor IDs to estimate directly
category
string
optional
Optional category to estimate across the current corpus
workload
object
required
Explicit workload assumptions for directional cost estimates. Missing fields become assumptions, not fabricated precision.
Recommends a complete stack from BuyAPI's corpus with a structured decision matrix, cost estimate, assumptions, unknowns, alternatives, and sources.
Use this when the user is starting a project or asks for a complete multi-layer stack choice. Do not use this for local coding/debugging/docs questions that do not involve software or vendor selection. Do not call vendors.resolve first; this tool handles retrieval and ranking.
Parameters5
projectDescription
string
required
What the user is building
constraints
string
optional
Budget, scale, existing tools, team size, compliance needs
workload
object
optional
Explicit workload assumptions for directional cost estimates. Missing fields become assumptions, not fabricated precision.
stackContext
array
optional
Optional existing stack context from a repo scan or saved private stack. Agents should pass derived tool metadata only, not source code.
stackFacts
object
optional
Optional derived stack facts such as languages, frameworks, runtimes, package managers, test tools, and dev workflow. Do not pass source code or secrets.
BuyAPI helps AI agents and developers make informed infrastructure decisions. When your agent needs to pick a database, auth provider, hosting platform, payment processor, email provider, or UI component system, BuyAPI provides current, structured, neutral vendor comparisons - not training data defaults.
Quick Start
Remote MCP (Recommended)
The hosted endpoint is the primary install path and exposes the current seven-tool contract.
This is the easiest path: the client connects directly to BuyAPI over HTTP, with no local process and no npm install.
CLI Setup
Run setup to install BuyAPI into your agent:
bash
npx buyapi
Bare npx buyapi opens an interactive setup flow. It asks which coding agent you use, installs the hosted MCP config by default, can add the /stack planning skill where supported, and can log you in for higher limits and stack sync.
/stack inspects the local repo, asks for missing constraints, calls BuyAPI MCP for current vendor data, and returns a sourced Stack Decision Record. It does not sync scan data unless you explicitly ask it to.
If you use the CLI often and do not want to type npx, install it globally:
bash
npm install -g buyapi
buyapi scan
In an MCP client config, use the explicit mcp command. The client launches it as a local stdio server; you do not run it manually first:
Use the local path when an agent client does not support remote MCP URLs, or when you want the open-source local transport. Hosted MCP is still the recommended default. The older buyapi-mcp package is deprecated on npm so new users see one canonical package name.
Stack Scan And Sync
The CLI has a stack scanner. Plain scan prints a local preview first, then asks
whether to save the private stack when the terminal is interactive:
bash
npx buyapi scan
Run it from the app, package, or monorepo root that contains project signals
such as package.json, a lockfile, framework config, convex/, prisma/,
Python manifests, or source imports. You can also point it at a public GitHub
repo URL:
bash
npx buyapi scan https://github.com/owner/repo
If no project signals are found, the CLI prints wrong-folder guidance instead
of silently returning an empty stack. Sync also skips stacks with zero known
BuyAPI tools unless you pass --allow-empty.
Use --verbose to see evidence and unknown package candidates found in
package.json:
bash
npx buyapi scan --verbose
For a guaranteed no-upload preview, use --dry-run. To save a private stack
without prompts in automation, login once, then sync:
bash
npx buyapi login
npx buyapi scan --sync --yes
Detection uses BuyAPI's own registry of manifest, marker-file, env-key,
config-content, import, framework, and language signals. Unknown runtime
packages are kept as candidates so the public tool register can learn about new
AI-native tools without copying third-party detection tables. Routine dev/build
tooling is filtered out before it reaches the review queue.
buyapi login opens the browser, signs in through the dashboard, creates a CLI API key, and stores it locally. You can still pass an existing key with buyapi login ba_live_... or use BUYAPI_API_KEY in CI. buyapi whoami --quiet exits 0 when a key is active and 1 when it is not. Sync uploads known detected tools plus filtered unknown package names, versions, and evidence so BuyAPI can review emerging tools. It does not upload source code, source file contents, or environment values.
scan is a human-facing CLI command, not an MCP tool. The MCP server should stay quiet on stdout because stdout carries the MCP protocol.
Read-Only CLI
The local package can query BuyAPI without starting an MCP client:
bash
npx buyapi search "realtime database with preview environments" --category database
npx buyapi details /database/convex
npx buyapi compare /database/convex /database/supabase --query "realtime SaaS"
npx buyapi recommend "B2B AI SaaS with teams and usage billing" --users 1000
npx buyapi cost /email/ses --emails 50000
Use --json on read-only commands to print the raw structured response.
When To Use BuyAPI
Use BuyAPI when the question is a vendor or stack decision:
txt
Should I use Convex, Supabase, or Neon for a realtime B2B SaaS?
txt
Estimate the email cost for 50,000 transactional sends/month.
txt
What auth provider should I use for organizations, SSO later, and a generous free tier?
Use implementation docs tools such as Context7 after the decision is made and the agent needs exact APIs, code examples, or version-specific setup steps.
Tips For Better Answers
Use BuyAPI vendor IDs when you know them, e.g. /database/convex, /database/supabase, /hosting/vercel.
Include workload numbers when asking about cost: users, monthly active users, email sends, storage, bandwidth, or monthly orders.
Include constraints that matter: solo founder, B2B SaaS, HIPAA/SOC2 later, no credit card free tier, preview environments, realtime collaboration, or low lock-in.
Ask for alternatives when you want tradeoffs, not just a single recommendation.
Search for vendors by query. Category is optional. Returns matching vendors with pricing summaries, positioning, confidence, and explicit unknown-corpus fallbacks.
code
Query: "I need a database for a real-time collaborative app"
Category: "database"
-> Returns: Convex, Supabase, Neon, PlanetScale, Firebase with comparison metadata
vendors.details
Get detailed vendor profile: concrete pricing numbers, free tier limits, scaling characteristics, known gotchas, source provenance, and head-to-head comparisons.
code
Vendor ID: /database/supabase
Query: "free tier limits for a side project"
-> Returns: Full pricing tiers, 500MB DB limit, 50K auth users, scaling triggers, and sources
vendors.evidence
Fetch recent reviewed evidence rows for a vendor, category, stack, or comparison.
code
Subject type: "vendor"
Subject ID: /database/supabase
-> Returns: Evidence summaries with source URLs, stance, confidence, and observed dates
stacks.findSimilar
Find public stack profiles related to a vendor, or recent curated stack examples.
code
Vendor ID: /database/convex
-> Returns: Similar stack profiles with project summary, audience, stage, tools, and confidence
vendors.compare
Compare two or more specific vendors for a workload or decision.
code
Vendor IDs: ["/database/convex", "/database/supabase", "/database/neon"]
Query: "realtime TypeScript SaaS with preview environments"
-> Returns: Structured decision matrix with fit, capability-by-capability yes/no/unknown coverage, tradeoffs, estimated cost, confidence, and sources
vendors.estimateCost
Run deterministic cost estimates from explicit workload inputs instead of leaving math to the model.
code
Vendor IDs: ["/email/ses"]
Workload: { "emailSendsPerMonth": 50000 }
-> Returns: Amazon SES estimated at $5/month, basis, assumptions, unknowns, and sources
stacks.recommend
Describe your project and get a complete stack recommendation with cost projections, a decision matrix, assumptions, unknowns, alternatives, and sources.
Use this for stack/vendor/tool decisions, not local implementation questions like CSS layout, TypeScript compiler errors, or framework API usage.
code
Project: "SaaS for restaurant inventory with real-time updates"
Constraints: "Solo founder, under $50/month until 1000 users"
Stack context: [{ "vendorSlug": "/database/convex", "category": "database", "confidence": "high" }]
-> Returns: Full stack (hosting + DB + auth + payments + email) with structured cost and decision data
BuyAPI currently works without an API key at the anonymous rate limit. Signed-in users can create dashboard API keys for keyed access, usage analytics, and stack sync.
The local package reads either BUYAPI_API_KEY or the key stored by buyapi login:
buyapi # Show setup guidance
buyapi setup <client> # Install MCP config for an agent
buyapi setup <client> --skill # Install MCP config and the /stack skill
buyapi setup-skill <client> # Install the /stack skill only
buyapi mcp # Run the local MCP server over stdio
buyapi login # Browser login and local key storage
buyapi login <api-key> # Store an existing API key
buyapi logout# Remove the stored API key
buyapi whoami# Verify the active local key
buyapi whoami --quiet # Auth check for scripts
buyapi scan [dir] # Scan locally, then optionally save stack
buyapi scan https://github.com/x/y # Scan a public GitHub repo
buyapi scan --sync --yes# Save detected tools without prompts
buyapi search <query> # Search vendors
buyapi details <vendorId> # Fetch one vendor profile
buyapi compare <ids...> # Compare vendors
buyapi recommend <prompt> # Recommend a stack
buyapi cost <ids...> # Estimate cost from workload flags
buyapi --version # Print the CLI version
Common flags:
bash
--category <name> Limit search/cost to a category
--query <text> Add workload or decision context
--client <name> Setup target: claude-code, cursor, codex, windsurf, cline
--local Write local stdio MCP config during setup
--skill Also install the /stack planning skill during setup
--print Print setup config instead of writing it
--name <text> Stack name for scan sync
--stack-name <text> Alias for --name
--stack <slug> Stable stack slug/name to update
--summary <text> Stack notes for scan sync
--sync Save scan output to your dashboard
--dry-run Preview scan output without uploading
--verbose Include scanner evidence details
--all Include lower-confidence supporting detections
--allow-empty Save even when no known tools were detected
--force Alias for --allow-empty
--yes Skip sync confirmation prompt
--users <n> Monthly active users
--emails <n> Email sends per month
--orders <n> Monthly orders
--json Print raw structured JSON
Covered Categories
Category
Vendors
Database
Supabase, Convex, Neon, PlanetScale, Firebase
Auth
Supabase Auth, Clerk, Auth0, Auth.js
Hosting
Vercel, Netlify, Railway, Fly.io
Payments
Stripe, LemonSqueezy, Paddle, RevenueCat
Email
Resend, SendGrid, Postmark, Amazon SES
UI Components
shadcn/ui
How It Works
This MCP server is a thin TypeScript client that calls the BuyAPI backend API. It contains no vendor data; lightweight comparison and cost formatting mirrors the hosted endpoint while vendor intelligence is served from buyapi.ai.
The source is fully open so you can verify there's no prompt injection or hidden behavior. scan previews locally first and only uploads after explicit confirmation or --sync; --dry-run never uploads. Sync sends detected tool metadata, derived stack context, checked file names, repo URL metadata when provided, and filtered unknown package candidates for review. It does not send source code or environment values.
Every profile shows when it was last updated and data source
BuyAPI does not accept payment from vendors for ranking influence
Inaccurate-data reporting, suggested edits, reviews, and vendor-claim requests exist behind moderation; vendor self-service editing is not live.
Troubleshooting
If your MCP client supports remote MCP URLs, use https://buyapi.ai/api/mcp first.
If remote MCP is not supported, configure the local stdio server with command: "npx" and args: ["-y", "buyapi", "mcp"].
Do not add banners or prompts to the stdio server command; stdout is reserved for MCP protocol messages.
If anonymous rate limits are hit, create an API key in the BuyAPI dashboard and pass it as BUYAPI_API_KEY where your client supports environment variables.
If a tool or vendor is missing, ask BuyAPI anyway. Unknown requests are treated as demand signals for future corpus expansion.
Disclaimer
BuyAPI profiles combine first-party sources, manual review, public evidence, and structured estimates. Vendor data can become stale or incomplete, especially pricing and limits. Use BuyAPI as a decision-support layer, verify critical production commitments directly with the vendor, and report outdated facts through the website when the reporting flow is available.
