set_active_project

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations declare readOnlyHint=false, idempotentHint=true and destructiveHint=false; the description is consistent with those and adds genuinely new context — that the selection is scoped to this stdio server instance and that null reverts to 'official-only' mode. It stops short of saying whether the selection persists across calls or what the response contains, but the added state model is valuable.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, front-loaded with the action and its scope, with the null-reset behavior immediately following. No filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be described. For a simple one-parameter stateful setter, the description covers the action, its scope, and the reset path. Minor gaps remain around persistence and where valid project_id values come from.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0% and the schema only declares project_id as a nullable string defaulting to null. The description compensates by explaining the null case ('return to official-only'), which the schema does not convey. It leaves open what a valid non-null project_id looks like (presumably an ID from list_projects), so not a 5.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Select a project') and adds the scoping context ('in this stdio server instance'), which distinguishes it from the read-only siblings list_projects and get_active_project. It's clear what the tool does, though it doesn't explicitly name the sibling it is not.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives one concrete usage rule — 'Pass null to return to official-only' — which tells the agent how to reset state. However, it never says when to call this versus list_projects/get_active_project, nor what prerequisites exist before selecting a project. Usage is implied rather than routed.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.