hub_role

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

Annotations already declare this is a non-destructive, idempotent write (readOnlyHint=false), so the safety profile is covered. The description contributes the dual-mode behavior (pass a role to assume it, pass none to read instructions) and implies owner-granted authority, but it omits what changes on assignment, whether it persists across calls, and what a successful call returns.

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?

A single short sentence with no filler and the mode-switch condition placed up front. It is efficiently sized; the problem is density of meaning, not length.

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?

With no output schema and no annotations describing effects, the description must explain what an agent gets back from each branch. It does not: the effect of assigning a role, the shape of the returned instructions, and persistence of the choice are all unstated for a tool operating on a multi-agent hub.

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 100% and the single optional parameter is fully enumerated in the schema, so the baseline is 3. The description adds one piece of meaning — that the "none" value yields the current role's instructions — but says nothing about the allowed values beyond what the schema lists.

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?

"Take a role" plus the "none" clause gestures at a role-assignment operation, but the sentence is a fragment that never states what the tool actually does — whether it sets the calling agent's persona, switches permissions, or simply retrieves instructions. It also does not distinguish itself from siblings such as hub_profile or hub_status, which plausibly overlap.

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 only guidance is the conditional "with none, see your role's instructions," which explains one parameter branch but not when to call the tool at all or why to choose it over hub_profile. No alternatives or preconditions are named.

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