MCP Server Builder
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
A skill your agent uses when the user wants to try BlockRun's free typed-judgment endpoint (POST api.blockrun.ai/v1/decide, served by OpenJev) on their own data from Claude Code — yes/no, labelled…
$ npx skills add BlockRunAI/blockrun-mcp --skill decide -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install BlockRunAI/blockrun-mcp decide --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/BlockRunAI/blockrun-mcp.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/decide .claude/skills/decide && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "decide" agent skill from https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decide into .claude/skills/decide/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "decide", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decideType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add BlockRunAI/blockrun-mcp --skill decide -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install BlockRunAI/blockrun-mcp decide --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/BlockRunAI/blockrun-mcp.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/decide .agents/skills/decide && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "decide" agent skill from https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decide into .agents/skills/decide/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "decide", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add BlockRunAI/blockrun-mcp --skill decide -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install BlockRunAI/blockrun-mcp decide --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/BlockRunAI/blockrun-mcp.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/decide .cursor/skills/decide && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "decide" agent skill from https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decide into .cursor/skills/decide/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "decide", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/BlockRunAI/blockrun-mcp.git --path skills/decide--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add BlockRunAI/blockrun-mcp --skill decide -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install BlockRunAI/blockrun-mcp decide --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/BlockRunAI/blockrun-mcp.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/decide .gemini/skills/decide && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "decide" agent skill from https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decide into .gemini/skills/decide/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "decide", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install BlockRunAI/blockrun-mcp decideInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add BlockRunAI/blockrun-mcp --skill decide -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/BlockRunAI/blockrun-mcp.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/decide .github/skills/decide && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "decide" agent skill from https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decide into .github/skills/decide/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "decide", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add BlockRunAI/blockrun-mcp --skill decide -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install BlockRunAI/blockrun-mcp decide --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/BlockRunAI/blockrun-mcp.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/decide .opencode/skills/decide && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "decide" agent skill from https://github.com/BlockRunAI/blockrun-mcp/tree/main/skills/decide into .opencode/skills/decide/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "decide", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
decideA skill your agent uses when the user wants to try BlockRun's free typed-judgment endpoint (POST api.blockrun.ai/v1/decide, served by OpenJev) on their own data from Claude Code — yes/no, labelled…
Decide is an agent skill from BlockRunAI/blockrun-mcp. Use when the user wants to try BlockRun's free typed-judgment endpoint (POST api.blockrun.ai/v1/decide, served by OpenJev) on their own data from Claude Code — yes/no, labelled choice, or scored-rung questions over a text or JSON state, up to 64 per call. Not an MCP tool: call it with curl from the shell. Covers the request shape, what the confidence number does and does not mean, and why OpenJev is not Jev.
Its SKILL.md is about 2.5k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in Agent Workflows, covering MCP servers. It works with Model Context Protocol. The repository describes itself as: Live data for AI agents — search, research, markets, crypto, X/Twitter. Pay-per-call via x402 micropayments. The licence is MIT.
4 steps, taken from the first numbered list in SKILL.md.
Read from SKILL.md and the folder at commit a7a9b3c. It shows what the files ask for, not the result of running them.
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Shell commands in SKILL.md call:
jqcurlFrom the folder's file list and the shell code blocks in SKILL.md.
Hosts in commands or code, which the agent is likely to contact:
api.blockrun.aiAlso links to:
blockrun.aiuser.blockrun.aiFrom URLs in SKILL.md, links to its own repository left out.
Names these keys or tokens, usually read from environment variables:
BLOCKRUN_API_KEYFrom names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Decide loads about 2.5k tokens when it runs. Until then it costs about 105 tokens; SKILL.md has 1,120 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
The full file from BlockRunAI/blockrun-mcp at commit a7a9b3c, republished under its MIT licence (© BlockRunAI). 1,120 words, ~2,465 tokens.
.claude/skills/decide/SKILL.md (or your agent's skills folder).POST https://api.blockrun.ai/v1/decide takes a state (a message, a ticket, a
diff, a tool result, a row of data) and up to 64 questions, and returns a typed
answer with a number beside each one. No prose to parse. The backend is
OpenJev, an open-source natural-language-inference model BlockRun hosts.
It is not a BlockRun MCP tool, on purpose: you are already a frontier model,
and for a one-off "is this urgent?" you are the better judge. The endpoint earns
its place when the user wants the same fixed ruler over many items, or is
prototyping a judgment they will later run from a pipeline without a model.
From Claude Code, call it with curl from the shell.
api.blockrun.ai, not the
x402 gateway at blockrun.ai (a POST to blockrun.ai/v1/decide is a 404).x-blockrun-backend response header names it on every call.Keys are minted at https://user.blockrun.ai/dashboard/keys (brk_live_…,
shown once; registration, not a card).
For experiments, export the key in the shell and leave the MCP server alone:
export BLOCKRUN_API_KEY=brk_live_…Do not write it to ~/.blockrun/.api-key just to try decide. The MCP
server reads that file at startup and a present key moves every paid tool
from wallet mode to account billing — the same switch BLOCKRUN_API_KEY in the
MCP server's own config makes. That is fine if the user wants account billing
(see the blockrun-setup skill); it is a surprise if they only wanted a free
judgment. If the MCP is already on account billing, the same key works for both.
curl -sS -X POST https://api.blockrun.ai/v1/decide \
-H "authorization: Bearer $BLOCKRUN_API_KEY" \
-H "content-type: application/json" \
-D /dev/stderr \
-d '{
"state": "Help! My payouts have been failing for 3 days.",
"questions": {
"is_urgent": { "type": "noul", "instructions": "Does this convey urgency?" },
"department": { "type": "choice", "instructions": "Which team should handle this?",
"criteria": { "billing": "Payments, refunds",
"technical": "Bugs, outages" } },
"frustration": { "type": "score", "instructions": "How frustrated is the customer?",
"criteria": ["Calm", "Frustrated", "Very angry"] }
}
}'-D /dev/stderr shows the response headers (backend, rate-limit) without mixing
them into the JSON on stdout.
| Field | Type | Required | Notes |
|---|---|---|---|
state | string | object | array | yes | What to judge. Text and JSON both work. If a fact matters, put it in the state — the model looks nothing up. |
questions | object | yes | Your own id → question. 1 to 64 per call. |
model | string | no | Defaults to openjev, the only backend. Leave it out. |
Three question types, one operation underneath (state = premise, question = hypothesis, answer = how strongly the premise entails it):
| Type | criteria | You get back |
|---|---|---|
noul | none — it is true or false | one number for how strongly the state supports the claim |
choice | map of label → its meaning, 2 to 255 entries | the top label, plus a share per option |
score | array of rung descriptions in words, 2 to 255 | a weighted position across the rungs, plus the distribution |
instructions — the question itself, in plain language — is required on all three.
{
"model": "openjev",
"answers": {
"is_urgent": { "type": "noul", "noul": 0.986 },
"department": { "type": "choice", "choice": "billing",
"probabilities": { "billing": 0.71, "technical": 0.29 },
"confidence": 0.71 },
"frustration": { "type": "score", "score": 1.42,
"legend": { "0": "Calm", "1": "Frustrated", "2": "Very angry" },
"probabilities": { "0": 0.11, "1": 0.36, "2": 0.53 },
"confidence": 0.53 }
}
}score is the probability-weighted rung index (1.42 sits between
"Frustrated" and "Very angry"); legend maps index → rung text.
The confidence on a choice is not the probability the answer is correct.
Every option is scored against the state, and the scores are then divided by their total so they sum to one. That step throws away how strong the scores were:
0.33 / 0.33 / 0.33;0.51 / 0.49.Opposite situations, identical response. The number is a share of the
agreement found — an ordering with a margin. Wide means the model clearly
preferred one option; narrow means it did not. It says nothing about whether
any option fits, and nothing has been fitted against real outcomes the way a
calibrated model's probabilities are. The same applies to score's
probabilities and confidence. A noul is the raw entailment score and is
not normalised — but it is not calibrated either.
Set thresholds by running the user's own labelled examples through the
endpoint and looking at where the errors land, never by reading the number as a
percentage. An agent that gates on confidence > 0.8 as if it were accuracy
will be wrong with no error to tell it so.
blockrun_exa
or blockrun_search first if a fact is missing; decide cannot look it up.blockrun_chat with
a claude-*, o-series or DeepSeek model — or to a person.A quick evaluation loop from Claude Code: put 20–50 labelled rows in a JSON
file, loop curl over them with jq, and tabulate agreement per question.
That is the only number that should decide whether the endpoint is good enough
for the user's task.
jq -c '.[]' examples.json | while read -r row; do
state=$(jq -c '.state' <<<"$row"); want=$(jq -r '.label' <<<"$row")
got=$(curl -sS -X POST https://api.blockrun.ai/v1/decide \
-H "authorization: Bearer $BLOCKRUN_API_KEY" -H "content-type: application/json" \
-d "{\"state\": $state, \"questions\": {\"q\": {\"type\": \"choice\",
\"instructions\": \"Which team should handle this?\",
\"criteria\": {\"billing\": \"Payments, refunds\", \"technical\": \"Bugs, outages\"}}}}" \
| jq -r '.answers.q.choice')
echo "$want,$got"
done | sort | uniq -cIt does not write, summarise, or explain — there is no free-text field in the response. It has no memory between calls. Image input exists in the model's v2 checkpoint but the endpoint does not expose it.
| Status | Meaning | What to do |
|---|---|---|
| 400 | Body did not match the schema; the response names the field | Fix the field. Common: a choice with criteria as an array, a score with a map, fewer than 2 criteria, more than 64 questions. |
| 401 | Missing or invalid key | BLOCKRUN_API_KEY is unset in this shell, or wrong. Check https://user.blockrun.ai/dashboard/keys. |
| 429 | Per-key hourly limit reached | Wait for the interval the response carries (retry-after). The limit is enforced server-side and reported in the response — read it there; do not assume a number. |
None of these cost anything; nothing here ever does.
blockrun-setup skill, "API key" section.© BlockRunAI, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Just SKILL.md in skills/decide of BlockRunAI/blockrun-mcp.
Open the folder on GitHubat commit a7a9b3c
Decide next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Decide this skillBlockRunAI/blockrun-mcp | 392 | — | ~2.5k | Automated safety check: Pass | MIT | |
| MCP Server Builderanthropics/skills | 180k | 62 repos | ~2.3k | Automated safety check: Pass | Apache-2.0 | |
| MCP Server BuildershareAI-lab/learn-claude-code | 78k | 5 repos | ~1.2k | Automated safety check: Pass | MIT | |
| MCP Integration for Pluginsanthropics/claude-plugins-official | 37k | 11 repos | ~3.1k | Automated safety check: Pass | Apache-2.0 | |
| Fastmcp Client CLIPrefectHQ/fastmcp | 28k | 1 repos | ~823 | Automated safety check: Pass | Apache-2.0 | |
| Crush Configurationcharmbracelet/crush | 29k | — | ~3.7k | Automated safety check: Pass | Custom licence |
anthropics/skills
Guides the design and implementation of Model Context Protocol servers in TypeScript or Python, from tool naming and error messages to evaluation.
shareAI-lab/learn-claude-code
Walks through building MCP servers in Python or TypeScript that expose tools, resources and prompts to Claude, with templates, registration and testing.
anthropics/claude-plugins-official
Explains how to bundle Model Context Protocol servers in a Claude Code plugin, covering config files, stdio, SSE, HTTP and WebSocket server types, and authentication.
PrefectHQ/fastmcp
Query and invoke tools on MCP servers using fastmcp list and fastmcp call.
charmbracelet/crush
Explains how to configure the Crush coding agent with crushrc or crush.json, covering providers, models, LSPs, MCP servers, hooks, permissions and config precedence.
mksglu/context-mode
Routes large command, file, API and browser output through context-mode tools so only the needed result enters the agent's context, instead of dumping it via Bash.
BlockRunAI/blockrun-mcp
Prepare or run a polished BlockRun trading demo that discovers a current Polymarket market, combines live price, probability history, smart-money, and liquidity evidence into a balanced signal…
BlockRunAI/blockrun-mcp
Pay-per-call access to AI models, real-time data, media generation and multi-chain RPC over x402 micropayments (USDC on Base or Solana), or a BlockRun account API key.
BlockRunAI/blockrun-mcp
A skill your agent uses when the BlockRun MCP server (@blockrun/mcp) is installed but misbehaving — 'Failed to connect', spawn npx ENOENT, blockrun missing from claude mcp list, HTTP 402 /…
BlockRunAI/blockrun-mcp
A skill your agent uses when asked to install, add, configure, or set up the BlockRun MCP server (@blockrun/mcp) in Claude Code, Claude Desktop, Cursor, Windsurf, Codex CLI, Grok or another MCP…
BlockRunAI/blockrun-mcp
A skill your agent uses when the BlockRun MCP server prints 'Update available', when asked to upgrade, update, or pin @blockrun/mcp, when a fix 'should be in the new version' but the client still…
BlockRunAI/blockrun-mcp
A skill your agent uses for any crypto data question — token/coin prices, FX, commodities, stocks, OHLC history, DEX pairs and liquidity, DeFi TVL, yield/APY pools, or raw JSON-RPC against a chain…
Works with
Categories
A skill your agent uses when the user wants to try BlockRun's free typed-judgment endpoint (POST api.blockrun.ai/v1/decide, served by OpenJev) on their own data from Claude Code — yes/no, labelled…. Decide is an agent skill from BlockRunAI/blockrun-mcp.ai/v1/decide, served by OpenJev) on their own data from Claude Code — yes/no, labelled choice, or scored-rung questions over a text or JSON state, up to 64 per call.
Decide fits situations like: the user wants to try BlockRuns free typed-judgment endpoint (POST api.blockrun.ai/v1/decide; served by OpenJev) on their own data from Claude Code — yes/no; labelled choice; scored-rung questions over a text.
Run `npx skills add BlockRunAI/blockrun-mcp --skill decide -a claude-code`. Or copy the skill folder (skills/decide in BlockRunAI/blockrun-mcp) into .claude/skills/decide in your project. Claude Code loads it when a task matches its description.
Run `npx skills add BlockRunAI/blockrun-mcp --skill decide -a codex`. Or copy the skill folder (skills/decide in BlockRunAI/blockrun-mcp) into .agents/skills/decide in your project. Codex loads it when a task matches its description.
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add BlockRunAI/blockrun-mcp --skill decide -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/decide, .gemini/skills/decide, .github/skills/decide and .opencode/skills/decide in your project.
Going by SKILL.md and its folder, Decide needs the command-line tools its instructions call (jq and curl) and credentials named BLOCKRUN_API_KEY. Our summary lists: A credential in BLOCKRUN_API_KEY.
SKILL.md names 3 domains. In commands or code: api.blockrun.ai; the agent is likely to contact it when it follows the instructions. As links in the text: blockrun.ai and user.blockrun.ai. This is read from the text; nothing was executed.
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
Decide is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
About 2.5k tokens (SKILL.md is roughly 9.9k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
Skills that share tags, products or a category with Decide: MCP Server Builder (anthropics/skills, 180k stars), MCP Server Builder (shareAI-lab/learn-claude-code, 78k stars), MCP Integration for Plugins (anthropics/claude-plugins-official, 37k stars) and Fastmcp Client CLI (PrefectHQ/fastmcp, 28k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
BlockRunAI (a GitHub organization) maintains it in BlockRunAI/blockrun-mcp, which has 392 GitHub stars. The repository holds 17 skills in this directory. The repository was last updated on October 6, 2026.
Source: BlockRunAI/blockrun-mcp on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.