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

Annotations already declare the mutation/safety profile (readOnlyHint=false, idempotentHint=false, destructiveHint=false), so the bar is lower. The description adds genuinely useful non-obvious behavior: the caller becomes owner, and the authorization prerequisite with a default role threshold.

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 compact sentence, front-loaded with the action and followed by the two facts an agent most needs (ownership outcome and permission). Zero 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?

For a simple two-param creation tool with no output schema, the description covers action, ownership side effect, tier, and authorization. Minor gaps (duplicate-name behavior, whether the new portfolio id is returned) are low-impact.

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% — both 'name' (min 2 chars) and optional 'description' are fully documented in the schema. The description adds no parameter syntax or format detail, so this is the baseline 3, not a penalty.

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 ('Create a portfolio') and immediately distinguishes it from siblings like update_portfolio and list_portfolios. The parenthetical feature-tier note adds scope precision without ambiguity.

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?

Gives the caller clear context: BUSINESS+ tier, required permission org.portfolio.manage with a default Manager+ role. It doesn't explicitly state when not to use it vs. update_portfolio or add_project_to_portfolio, so it stops just short of full routing guidance.

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