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

With no annotations, the description carries the burden well: it discloses the sign-in prerequisite, the side effect (creates an own_profile stream pointing at the same posts), the free-plan scoping, and an explicit refusal condition. It stops short of saying what happens on paid plans or whether the created stream can be undone, but the mutation profile is largely covered.

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?

Three compact sentences with the core action front-loaded, followed by prerequisite and failure condition. No wasted words and nothing buried.

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?

For a one-parameter mutation tool with no annotations or output schema, the description covers prerequisite, side effect, scope, and refusal case. Minor gaps remain around reversibility and non-free-plan behavior, but an agent can call it correctly from this text.

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?

Single parameter with 100% schema description coverage, so the schema already explains preview_id. The description reinforces that the id comes from preview_profile but adds no format or edge-case detail beyond that, so baseline 3 applies.

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 ('Make a profile from preview_profile your own Flux dashboard') and names the downstream artifact ('own_profile stream'). It distinguishes itself from both preview_profile (inspection) and create_stream (generic stream creation) by tying the two together.

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?

Clear context of use: requires sign-in and it 'Refuses if you already track that profile' gives an explicit when-not condition. It does not explicitly say 'run preview_profile first to get a preview_id', though that is implied by the purpose sentence.

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