io.github.nexus-mcp-infra/similarity-search-api-sdk
REMOTE · SIMILARITY-SEARCH-API-PRODUCTION.UP.RAILWAY.APP · SCANNED AUG 3
Stateless NMI + cosine fusion with entropy-driven alpha calibration
Available components
How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. How we score →
Endpoint Security57
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- Authorisation not fully verified: no authorisation is required to call this server, and 3 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe. See how to fix → View diagnostics → Unverified
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability55
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 964 tokens (~321/item across 3 items; 3 tools + 0 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management27
- Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Capabilities100
- Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Add this component to your MCP client. Where a client-specific snippet is available, pick your client below and copy it straight into your config; otherwise use the connection detail shown.
remote · similarity-search-api-production.up.railway.app
claude mcp add --transport http nexus-mcp-infra-similarity-search-api-sdk https://similarity-search-api-production.up.railway.app/mcp
[mcp_servers.nexus-mcp-infra-similarity-search-api-sdk] url = "https://similarity-search-api-production.up.railway.app/mcp"
{
"$schema": "https://opencode.ai/config.json",
"mcp": {
"nexus-mcp-infra-similarity-search-api-sdk": {
"type": "remote",
"url": "https://similarity-search-api-production.up.railway.app/mcp",
"enabled": true
}
}
} openclaw mcp add nexus-mcp-infra-similarity-search-api-sdk --url https://similarity-search-api-production.up.railway.app/mcp --transport streamable-http
mcp_servers:
nexus-mcp-infra-similarity-search-api-sdk:
url: "https://similarity-search-api-production.up.railway.app/mcp" {
"mcpServers": {
"nexus-mcp-infra-similarity-search-api-sdk": {
"type": "http",
"url": "https://similarity-search-api-production.up.railway.app/mcp"
}
}
} The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.
Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.
- 3 Aug 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.
- 1 Aug 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.
- 31 Jul 26 0
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 30 Jul 26 +1
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 29 Jul 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.
- 27 Jul 26 +1
- We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
- 26 Jul 26 58
First indexed and scored.
Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.
Captured 3 Aug 2026 · Probed https://similarity-search-api-production.up.railway.app/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=*.up.railway.app | CN=YE1,O=Let's Encrypt,C=US | 29 Jul 2026 | 27 Oct 2026 | ECDSA 256 | ECDSA-SHA384 | 6da79bb561da3efeb0e751ca21abd3999fe |
| SANs: *.up.railway.app, up.railway.app | ||||||
| CN=YE1,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 5ddd70dd31f801c85c186a7a04b80afe |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
DNSSEC insecure
Validation of similarity-search-api-production.up.railway.app. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| app. | present | 23684 | 8 | Verified |
| railway.app. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://similarity-search-api-production.up.railway.app/mcp | Verified | 200 | |
| http (plaintext) | http://similarity-search-api-production.up.railway.app/mcp | HTTPS enforced | 301 | https://similarity-search-api-production.up.railway.app/mcp |
The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability.
nexus_similarity_search_api_estimate_corpus_entropy_profile ~253
Computes the aggregate entropy-calibrated alpha for a corpus without running a full search -- useful to inspect before committing to a large rank_items_by_nmi_cosine_fusion call. Returns a single aggregate corpus_entropy value, NOT a per-dimension breakdown -- the real logic only exposes the mean marginal entropy across dimensions, not H(X_d) per individual dimension. Do NOT use expecting per-dimension granularity. Requires a valid api_key (same as X-API-Key) and an x402 payment.
| Name | Type | Req | Description |
|---|---|---|---|
| api_key | string | yes | API key required for this paid operation -- same secret configured as X-API-Key on the REST endpoints (SIMILARITY_API_KEY). Payment (x402) alone is not sufficient; both gates must pass. |
| corpus_vectors | array | yes | List of dense numeric vectors for which to compute the aggregate entropy and calibrated alpha. Each inner array must be the same length. Maximum 500000 entries. |
| n_bins | number | — | Number of histogram bins for entropy discretization. Must be between 3 and 50; should match the n_bins used in rank_items_by_nmi_cosine_fusion for the profile to be consistent. |
Structured output declared, but exposes no named fields.
No examples provided.
nexus_similarity_search_api_rank_items_by_nmi_cosine_fusion ~399
Ranks a corpus of items against a query vector using a calibrated fusion score (alpha * cosine + (1-alpha) * NMI_normalizado), where alpha is auto-derived from the corpus's marginal entropy unless overridden. Results are identified by their 0-indexed position in corpus_vectors (this tool does not accept explicit item IDs). Use this when you need semantically-calibrated similarity over a stateless corpus of up to 500k items without a vector database. Do NOT use for purely geometric nearest-neighbor search where NMI overhead is unnecessary, nor for corpora larger than 500k items per call. Requires a valid api_key (same as X-API-Key) and an x402 payment.
| Name | Type | Req | Description |
|---|---|---|---|
| alpha_override | number | — | Fixed alpha weight for cosine component in [0.0, 1.0]. If omitted, alpha is auto-calibrated from corpus entropy. Set to 1.0 to use pure cosine; 0.0 for pure NMI. |
| api_key | string | yes | API key required for this paid operation -- same secret configured as X-API-Key on the REST endpoints (SIMILARITY_API_KEY). Payment (x402) alone is not sufficient; both gates must pass. |
| corpus_vectors | array | yes | List of dense numeric vectors forming the corpus to rank against. Each inner array must match query_vector dimensionality. Maximum 500000 entries. |
| n_bins | number | — | Number of histogram bins used to discretize continuous dimensions when estimating NMI. Must be between 3 and 50. |
| query_vector | array | yes | Dense numeric vector representing the query item. Must have the same dimensionality as all corpus_vectors entries. |
| top_k | number | — | Number of top-ranked results to return, ordered by descending fusion score. Capped at 1000 by the core service regardless of corpus size. |
Structured output declared, but exposes no named fields.
No examples provided.
nexus_similarity_search_api_score_pair_nmi_cosine ~312
Computes the NMI-cosine fusion score for exactly one (query, target) vector pair at a fixed alpha. Use for explainability, debugging, or unit-level validation of fusion scores before running full corpus ranking. Unlike corpus-level ranking, alpha is NOT auto-calibrated for a single pair -- the real logic requires a fixed alpha (default 0.5); pass alpha explicitly for a specific blend. Do NOT use in a loop to score many pairs; batch them into rank_items_by_nmi_cosine_fusion instead. Requires a valid api_key (same as X-API-Key) and an x402 payment.
| Name | Type | Req | Description |
|---|---|---|---|
| alpha | number | — | Fixed alpha weight for the cosine component in [0.0, 1.0], applied as-is -- not auto-calibrated. Default 0.5 matches the core service default. |
| api_key | string | yes | API key required for this paid operation -- same secret configured as X-API-Key on the REST endpoints (SIMILARITY_API_KEY). Payment (x402) alone is not sufficient; both gates must pass. |
| n_bins | number | — | Histogram bins for NMI discretization. Must be between 3 and 50. |
| vector_a | array | yes | First dense numeric vector of the pair. Must have the same dimensionality as vector_b. |
| vector_b | array | yes | Second dense numeric vector of the pair. Must have the same dimensionality as vector_a. |
Structured output declared, but exposes no named fields.
No examples provided.