Admins can now give each EXTERNAL MCP server a free-text instruction ("how/
when to use this server's tools") that the agent receives in its SYSTEM
PROMPT next to the tool descriptions — porting the built-in SERVER_INSTRUCTIONS
idea to admin-configured servers. Trusted, admin-authored text (like a system
prompt); NON-secret, so unlike headersEnc it IS returned in views/forms.
- Migration: nullable `instructions text` on ai_mcp_servers (old rows = null =
no guidance). Table type + repo insert/update (blank/whitespace -> null via
blankToNull). DTO `@MaxLength(4000)`. Service threads it through
McpServerView/toView.
- mcp-clients: `McpServerInstruction { serverName, toolPrefix, instructions }`
threaded through the toolset/cache/lease. Guidance is built ONLY for a server
that actually connected AND contributed >=1 callable tool (the allowlist may
filter all of them out) AND has non-blank text — so a guide never appears for
tools the agent cannot call. Cached with the toolset, so an edit is picked up
next turn via the existing CRUD cache invalidation.
- System prompt: `buildMcpToolingBlock` renders an <mcp_tooling> block INSIDE
the safety sandwich (after context, before the trailing SAFETY_FRAMEWORK) so
it informs tool choice but cannot override the rules; each section is headed
by the server's `prefix_*` namespace. Empty/blank -> block omitted. The
caller (ai-chat.service) now builds the external toolset BEFORE the prompt and
passes external.instructions; client-handle lifecycle (close-once) unchanged.
- Client: instructions field in types + a Textarea (autosize, maxLength 4000)
in the MCP-server form with a namespace-prefix hint; i18n (en/ru).
Tests across every layer (prompt block placement + both SAFETY copies; view
blank->null; buildEntry includes guidance only for connected+>=1-tool+non-blank;
DTO MaxLength; repo + integration round-trip; service wiring). Delegated impl
reviewed (APPROVE); applied the import-type follow-up.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
A progressive Node.js framework for building efficient and scalable server-side applications.
Description
Nest framework TypeScript starter repository.
Installation
$ npm install
Running the app
# development
$ npm run start
# watch mode
$ npm run start:dev
# production mode
$ npm run start:prod
Migrations
# This creates a new empty migration file named 'init'
$ npm run migration:create --name=init
# Generates 'init' migration file from existing entities to update the database schema
$ npm run migration:generate --name=init
# Runs all pending migrations to update the database schema
$ npm run migration:run
# Reverts the last executed migration
$ npm run migration:revert
# Reverts all migrations
$ npm run migration:revert
# Shows the list of executed and pending migrations
$ npm run migration:show
## Test
```bash
# unit tests
$ npm run test
# e2e tests
$ npm run test:e2e
# test coverage
$ npm run test:cov
Support
Nest is an MIT-licensed open source project. It can grow thanks to the sponsors and support by the amazing backers. If you'd like to join them, please read more here.
Stay in touch
- Author - Kamil Myśliwiec
- Website - https://nestjs.com
- Twitter - @nestframework
License
Nest is MIT licensed.