In-depth architectural comparison of the Agent Nexus and Openapi MCP Server MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.
At a Glance & Executive Verdict
Agent Nexus
Developer Tools · Local stdio
Quality: 50/100 (Good) | Auth: No auth required
Openapi MCP Server
Developer Tools · Remote HTTP/SSE
Quality: 47/100 (Fair) | Auth: No auth required
Verdict Summary: Choose Agent Nexus if you need specialized Developer Tools tools running via a local process. Choose Openapi MCP Server if your workspace requires Developer Tools integration with remote web transport. Both servers can be configured concurrently in your client's mcpServers manifest.
Which MCP Server Should You Choose?
A
Choose Agent Nexus when:
You need dedicated capabilities in the Developer Tools domain.
You prefer local stdio subprocess transport architecture.
Your security boundary fits: No auth required (Free / Open Source).
Map a plain-language goal (e.g. 'send a transactional email') to callable APIs, MCP servers or CLIs. Returns {need, coverage, count, uncovered, note, matches[]}; each match has slug, endpoint, auth, formats, rate limit, pricing and a 0-100 reliability score. Never empty on a valid need: if nothing fits, coverage='none' and matches[] lists reliable starting points. Errors: an invalid or too-short need fails input validation; a backend failure returns isError=true with the message. Rate limits: 100 calls/day anonymous, 1,000/day with a free key (POST /api/public/keys, no account), 50,000/day on Agent Pro. For a known keyword or slug, use search_registry.
search_registry
Keyword lookup in the Agent Nexus registry when you already know what to look for: a product name, vendor, slug or endpoint fragment, optionally narrowed to one category. Matches literal text only — it does not interpret a goal. To go from a plain-language need to a callable interface, use discover_capabilities instead; to walk the whole catalogue in order use list_entries, and for the full record of one known slug use get_entry. Returns {count, results[]} in summary form, and an empty results[] when nothing matches — that is a valid answer, not an error.
get_entry
Fetch the full record of ONE approved registry entry whose exact slug you already have, e.g. from a previous discover_capabilities, search_registry or list_entries result. Read-only and idempotent: the same slug always returns the same entry until its health probe changes. Returns {entry} with endpoint, auth mode and parameters, input/output formats, rate limit, pricing, capabilities, docs URL, invocation example and the latest 6-hourly health probe — the detail level the listing tools omit. This is the single-record lookup: it takes no filters and no paging. If you do not have a slug, do not guess one — use search_registry for a keyword or discover_capabilities for a plain-language need; to walk the whole catalogue use list_entries. An unknown or unapproved slug is an error, not an empty result.
Ready-to-Paste Client Configurations
Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).
Agent Nexus is categorized under Developer Tools and uses a local stdio subprocess. In contrast, Openapi MCP Server belongs to Developer Tools using remote streaming HTTP/SSE transport. Select Agent Nexus when you need capabilities focused on developer tools and Openapi MCP Server when you require tools for developer tools.
Return the fixed taxonomy of Agent Nexus: the three interface layers it indexes ('api', 'mcp', 'cli'), each with a label, a one-line definition and its live count of approved entries. Read-only, idempotent and parameterless — call it once to learn the exact values accepted by the 'category' argument of search_registry, list_entries and discover_capabilities, and to size the catalogue before paging. It never returns entries themselves: use list_entries to enumerate a layer, search_registry for a keyword, discover_capabilities for a plain-language need.
list_entries
Enumerate the whole approved catalogue in deterministic slug order, page by page — use this when you want everything (mirroring, auditing, building your own index), not when you are looking for something specific. Read-only and idempotent. Returns {total, page, per_page, pages, results[]}: read 'pages' from the first response and increment 'page' until you reach it; 'total' and 'pages' reflect the 'category' filter when one is set, so keep the filter identical across pages or the paging shifts. Entries come back in summary form; call get_entry with a slug for the full record. For a keyword use search_registry, for a plain-language need use discover_capabilities, and for the accepted category values call list_categories. Bulk mirror alternative: GET https://agentnexus.app/api/public/entries.ndjson streams the full catalogue in one request.
submit_entry
Register a new interface (HTTP API, MCP server or CLI) in the Agent Nexus catalogue. Callers authenticate either as a signed-in member or with a free agent key (POST https://agentnexus.app/api/public/keys), which allows one submission per key and per source address per 24 hours. This is a write: it creates a pending row, it does NOT publish anything — every submission is reviewed by a human before it becomes discoverable, so nothing you send here is visible to other agents until it is approved. Nothing is overwritten or deleted, and re-submitting the same name creates a second pending row rather than updating the first. Five fields are required (name, category, summary, endpoint, auth_mode); everything else is optional but directly decides whether the entry is approved and how well it ranks: capabilities[] is what other agents are matched against, so list concrete verbs, and docs_url plus invocation_example are what a reviewer checks first. Rate limited to 20 submissions per hour for members and 1 per 24 hours per agent key and per source address, and the endpoint must answer a live health probe to keep a reliability score. Returns {slug, status}; poll GET https://agentnexus.app/api/public/submission?slug=<slug> for the decision, or pass contact_email to be emailed instead. Use list_my_submissions to review what you already submitted; use search_registry first to check the interface is not already listed.