get_context is the context gate on the 📝MythOS MCP server: the MCP tool that loads a user's augmentation memos — Soul, Style, Human, and Memory — into an agent session as the L0 Identity + L1 Personal context tier. The server enforces it in tool dispatch: every tool except get_context itself is blocked until it has been called for the session's API key.

Key Facts

Tier: L0 (Soul + Style) and L1 (Human + Memory), loaded together in one call
Inputs: none — the transport resolves the target library, defaulting to the API key's owner
Output format: a single markdown document titled # Augmentation Context with ## Mythos Soul, ## Mythos Style, ## Mythos Human, ## Mythos Memory sections (each trimmed to 4,000 characters), followed by a ## Memo Path Convention section covering the slash-vs-dash memo id forms and the tool input contract
Gate: enforced in dispatch, not in tool descriptions — any other tool called first returns a GET_CONTEXT_REQUIRED instruction to call get_context and retry the original call unchanged. The gate response is a plain tool result, deliberately not an MCP error, so clients that discard error text still surface the retry instruction; genuine failures still set isError
Gate lifetime: a successful call unlocks tools for that API key for up to 24 hours; the state is in-process, so a server restart or redeploy re-arms the gate mid-session
Source of the four memos: the user's augmentation settings; each is also exposed as an MCP resource at augmentation://soul|style|human|memory, and additional #mythos-mcp-context-tagged memos are resources at augmentation://memo/<id> — loaded on demand, never inserted into the get_context response

How It Works

The transport resolves the session's user before any tool runs — the HTTP endpoint verifies the API key or OAuth token at the door, and the stdio binary fetches augmentation at startup. When an agent calls get_context, the server marks the gate satisfied for the API key, concatenates whichever of Soul/Style/Human/Memory are populated under a framing paragraph ("Apply the Mythos Style rules to all memo operations. Apply the Mythos Soul values to all interactions."), and appends the Memo Path Convention. Any other tool called before that returns GET_CONTEXT_REQUIRED: This is a context gate, not a bad tool argument… — the correct client behavior is to call get_context, then retry the original tool unchanged.

Why It Matters

The tool is how the scope-locality architecture bootstraps every session: it guarantees the agent enters any task already holding the user's formatting rules, collaboration values, current life context, and durable memory — the four layers every downstream decision depends on. Without it, create_memo would write memos that violate the user's Style rules, and the agent would operate without the preferences recorded in Memory. Because the gate binds in dispatch, an agent cannot skip it by starting with a read: the first substantive call of any session routes through get_context. Keeping the default payload to the four core memos keeps it small; project-specific augmentation loads on demand as MCP resources when the conversation narrows onto it.

FAQ

When must get_context be called?

Before any other tool call in a session — reads included. The gate is enforced in dispatch for every tool except get_context itself. It can also reappear mid-session after a server restart or redeploy; the fix is always the same — call get_context, then retry the original tool unchanged.

Does get_context accept a username or library parameter?

No. The tool takes no arguments. The header-auth HTTP transport resolves the target library from a ?username= query param or x-mythos-username header when present, subject to library-grant authorization, and otherwise from the key's owner; OAuth sessions are fixed to the token's user. Other tools accept a library parameter for cross-library reads.

What happens if the user has not configured augmentation?

The tool returns "No augmentation context configured. The user has not set up their augmentation memos yet." plus the Memo Path Convention, and the gate still unlocks. Write tools will run, but without Style rules loaded the output will drift from conventions.

Is there a token-budget footer or an L2 tier?

Not anymore. Earlier builds appended a budget footer and advertised a load_context_tier follow-up; both are gone. The response is the four core sections plus the path convention, and extended #mythos-mcp-context memos are available as MCP resources instead.

Subjective

This is the single most load-bearing tool in the MCP surface — every session routes through the Style rules it delivers. Moving the gate into dispatch made it the right shape: cheap to enforce, impossible to forget, and it makes the augmentation memos the actual governance layer rather than aspirational documentation.