MongoDB stores records as documents, which group related field values in one JSON-like structure. A collection holds documents, and BSON is the binary encoding that supports values such as dates and ObjectIds. An ObjectId is a common identifier format with a timestamp component, but it is not an authorization mechanism or a strict business ordering guarantee.

Foundation2 min read

What makes JWT or session authentication safe?

Performance & security·Security

Token and session security means accepting only credentials issued by a trusted authority for the intended purpose and lifetime. A JWT can carry verifiable claims, while a server session uses stored state behind a session identifier. Both need secure transport, controlled storage, expiry and a response to credential theft.

Intermediate2 min read

How should I store passwords and secrets?

Performance & security·Security

Password hashing turns a password into a one-way verification value using an intentionally expensive algorithm. Secret management protects credentials that the application must be able to use again, such as database passwords or API keys. Passwords should not be reversibly encrypted just so they can be compared at login.

Intermediate2 min read

MCP tools and tool discovery

AI Engineering·Model Context Protocol (MCP)

A tool is a named executable capability with argument metadata and a schema. Discovery lets a client obtain the server's available tool descriptions. A tool description helps the model choose a capability; it is not proof that the server or tool is…

Intermediate2 min read

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