From docs to done.
The docs are a maze and the threads are noise. ToolCall takes one concept a week and draws the line straight through it — so you actually understand the tool before you ship with it.Learn fast.
30–60 seconds. One concept, one mental model, no preamble.
Skip the trap.
The gotcha that bites in production — before it bites you.
Keep the good ones.
Save the breakdowns worth re-reading. A reference you build, one a week.
We don't decorate.
We explain.
Every concept gets the same treatment: name it, draw it, show the one rule that breaks it. Checked by someone who builds with these tools — no generic AI filler.
What we explain
all concepts →MCP & tools
How models actually reach your data and systems — the M×N → M+N problem it solves, the three primitives, the transports.
read →Agents
The loop behind the buzzword: think, act, observe, repeat — and where it quietly goes wrong.
soonCost & caching
Prompt caching, token math, and the structure choices that cut cached-input cost by ~10×.
soonRAG & context
Retrieval, chunking, context engineering — what to put in the window and what to leave out.
soonHow each one is made
// the methodOne concept
The thing devs keep getting wrong this week.
Owner-checked
Every claim signed off by a practitioner.
Built to show
The mechanism animated, not narrated over stock.
Save & reuse
60 seconds you can act on, then keep.
Get MCP in one page.
Free.
The diagram, the three primitives, a runnable starter — then one concept a week.
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