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Practical notes on human-reviewed AI agents.

Payload-powered product notes, security writing, HITL patterns, and operational guidance from the Facio runtime: long sessions, Placet approvals, audit trails, memory, providers, channels, tools, and Docker-first operations.

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Showing 11-15 of 76 articles in Engineering.

Engineering

MCP Spotlight: Time MCP Server — Anthropic's Reference Implementation for IANA Timezone Conversion, DST-Aware Math, and the DateTime-Default Reference for Agents

Jul 25, 2026Engineering

MCP Spotlight: Time MCP Server — Anthropic's Reference Implementation for IANA Timezone Conversion, DST-Aware Math, and the DateTime-Default Reference for Agents

The official Time MCP Server by Anthropic — 2 tools (get_current_time, convert_time) backed by the IANA tzdata database. DST-aware transitions, historical accuracy back to early 1900s, ~400 zones, alias support. The timezone-aware time-math default for AI agents in 2026. MIT-licensed, available via uvx or Docker.

Engineering

MCP Spotlight: PostgreSQL MCP Server — The Database Bridge With Read-Only Default, Query Allow-List, Parameterized Statements, and the Schema-Aware Default for Agents

Jul 24, 2026Engineering

MCP Spotlight: PostgreSQL MCP Server — The Database Bridge With Read-Only Default, Query Allow-List, Parameterized Statements, and the Schema-Aware Default for Agents

The official PostgreSQL MCP Server by Anthropic — ~12 focused tools (list_schemas, list_tables, describe_table, query, explain). Read-only is the default, write-mode requires explicit opt-in with statement-type filtering. Parameterized queries via $1, $2 placeholders (SQL injection impossible). MIT-licensed.

Engineering

MCP Spotlight: Fetch MCP Server — Anthropic's Reference Implementation for HTML-to-Markdown Web Reading, Length-Bounded Retrieval, and the Web-Content-Default for Agents

Jul 23, 2026Engineering

MCP Spotlight: Fetch MCP Server — Anthropic's Reference Implementation for HTML-to-Markdown Web Reading, Length-Bounded Retrieval, and the Web-Content-Default for Agents

The official Fetch MCP Server by Anthropic — 1 tool (fetch), HTML-to-Markdown conversion, length-bounded output (default 5000 chars), agentjacking defense, read-only safety. The web-content-reading default for AI agents in 2026. MIT-licensed, available via NPX or Docker.

Engineering

MCP Spotlight: Slack MCP Server — The Official Team-Communication Bridge With LLM-Native Tool Design, Channel-Add Allow-List, and the Conversation-Default Reference for Agents

Jul 22, 2026Engineering

MCP Spotlight: Slack MCP Server — The Official Team-Communication Bridge With LLM-Native Tool Design, Channel-Add Allow-List, and the Conversation-Default Reference for Agents

The official Slack MCP Server by Slack — ~30+ LLM-native tools (built for LLM consumption with rich descriptions, natural-language responses, examples, pre/post-call hints). Posting disabled by default, enabled per-channel via explicit allow-list. OAuth 2.0 with principle-of-least-privilege scopes. MIT-licensed.

Engineering

MCP Server Authoring Guide 2026: Building Production-Grade MCP Servers From Scratch — The Authoring Playbook Every Independent Server Author Should Follow

Jul 21, 2026Engineering

MCP Server Authoring Guide 2026: Building Production-Grade MCP Servers From Scratch — The Authoring Playbook Every Independent Server Author Should Follow

The 12 decisions every MCP server author must make: transport, SDK, license, auth, secrets, tool surface, output format, error handling, rate limiting, idempotency, distribution, documentation. Plus standard patterns (pagination, search, bulk, async, webhooks), security hardening, testing strategy, versioning, and the publishing checklist.