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Local stdio bridge to the hosted GridHub electricity market data MCP server. Provides access to real-time and historical electricity price, demand, generation, carbon intensity, and capacity data across 25 global grid zones.
GridHub MCP demonstrates solid definition quality with well-structured tool schemas, comprehensive parameter descriptions, and clear authentication guidance. All 6 tools have explicit input schemas with proper JSON Schema format and enum constraints. Descriptions are detailed (194 - 400+ chars) and include actionable context (e.g., 'Call this first if unsure which zone id to use' for list_zones). Tool annotations are present and correct (readOnlyHint=true for all). However, output schemas are not documented, LLMs cannot see what fields to expect from responses. Parameter descriptions are verbose but could be more concise. Error handling guidance is minimal; no recovery paths or actionable error messages are visible in the definitions.
Time series for one metric in one zone over a start/end window (Unix seconds). Rows are returned oldest-first and the 'limit' truncates from the OLDEST end, so a small limit over a wide window returns old data, not recent data — for 'the latest N points' set start close to now, or use get_latest / get_zone_brief for current values. Default window is the last 24h (last ~400 days for capacity, which is annual). Max window 31 days per call (400 for capacity); paginate with start/end for more. Metrics: price (wholesale, local currency per MWh), demand (MW), generation (per fuel, 'fuel' field set; % or MW depending on zone; GB and US-CAISO only), carbon-intensity (gCO2/kWh; GB only), interchange (net imports, MW), capacity (installed MW per fuel; European zones only). Authentication: send 'Authorization: Bearer <ghk_key>' on the MCP connection (free key, 500 requests/day, instant email signup at https://grid-hub.app/developers), or pay per call with x402 (USDC on Base) via the X-PAYMENT header. With no credentials, data tools run in free sample mode: real, current data but truncated (history capped at 50 rows; brief returns one context block). Sample results are clearly marked.
The most recent value of every metric one zone publishes (price and demand for every zone; generation by fuel for GB and US-CAISO; carbon intensity for GB; interchange where available), each with unit and timestamp. This is the right tool for 'what is the price/demand/carbon intensity in X right now'. Note: some European sources publish day-ahead prices, so the price timestamp can be up to ~36h in the future; use get_zone_brief for a strictly at-or-before-now value with historical context. Authentication: send 'Authorization: Bearer <ghk_key>' on the MCP connection (free key, 500 requests/day, instant email signup at https://grid-hub.app/developers), or pay per call with x402 (USDC on Base) via the X-PAYMENT header. With no credentials, data tools run in free sample mode: real, current data but truncated (history capped at 50 rows; brief returns one context block). Sample results are clearly marked.
Output schemas not documented. LLMs cannot see what fields responses contain, forcing them to guess at downstream tool chaining and data extraction.
No error handling guidance in tool descriptions. When a tool fails (e.g., invalid zone, auth failure, rate limit), LLMs have no recovery path documented.
API key parameter exposed in tool input schema. Best practice is server-side secret injection via Authorization header (which is already supported). The api_key parameter should be removed to prevent credentials from appearing in logs.
Inferred effective spec: 2026-07-28+.
| Scored | Grade | Overall | Spec posture | Rubric |
|---|---|---|---|---|
| 2026-09-23 | C | 64 | 2026-07-28+ | v2 |
Current headline values for all 25 zones in one call — the cheapest way to compare zones (e.g. 'which European zone has the lowest price right now', 'rank US ISOs by demand'). Rebuilt every 5 minutes. Authentication: send 'Authorization: Bearer <ghk_key>' on the MCP connection (free key, 500 requests/day, instant email signup at https://grid-hub.app/developers), or pay per call with x402 (USDC on Base) via the X-PAYMENT header. With no credentials, data tools run in free sample mode: real, current data but truncated (history capped at 50 rows; brief returns one context block). Sample results are clearly marked.
Ingestion health per source and zone: last successful fetch timestamp and last error, if any. Free. Use it to explain stale or missing values before drawing conclusions from them.
Composite, interpretation-ready snapshot of one zone: current price / demand / carbon intensity where published (strictly at-or-before now), each ranked against that zone's own last ~30 days (percentile, vs-median %, min/max, sample count and the actual data window), a 24h trend per metric, the generation mix where published (GB, US-CAISO), and a one-sentence plain-English summary. Best tool for questions like 'is electricity cheap/clean in X right now' or 'is this a good time to run a flexible workload'. A raw price means little without this context. Authentication: send 'Authorization: Bearer <ghk_key>' on the MCP connection (free key, 500 requests/day, instant email signup at https://grid-hub.app/developers), or pay per call with x402 (USDC on Base) via the X-PAYMENT header. With no credentials, data tools run in free sample mode: real, current data but truncated (history capped at 50 rows; brief returns one context block). Sample results are clearly marked.
List the 25 electricity grid zones GridHub covers, with id, name, data source (EIA, ENTSO-E, NESO, AEMO), timezone, currency, licence and required attribution. Free, no credentials needed. Call this first if you are unsure which zone id to use.
Parameter descriptions are verbose (AUTH_NOTE repeated 4 times, 300+ chars). Descriptions should be 10 - 1024 chars; these exceed best practice and waste tokens. Consolidate authentication guidance into server documentation.
No pagination or result-limiting guidance in tool descriptions. get_history accepts limit (1 - 1000) but does not explain the MCP_HISTORY_MAX=1000 cap or how to paginate large windows.