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

Annotations already declare a non-read-only, non-destructive, non-idempotent write, so the safety profile is covered. The description adds genuine value beyond them: it discloses the return shape ({ id }), the empty starting state, and the cost profile ('FREE: database only, no SEO data provider is called and no credits are spent') — a real operational trait an agent could not infer from structured fields.

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 short sentences, zero filler, each carrying distinct information (what it does, what it returns, what to do next, and what it costs). The next-step guidance and cost note are front-loaded rather than 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?

No output schema exists, but the description supplies the return value ({ id }), the follow-up action, and the cost/credit implication, which is everything an agent needs to invoke this simple single-parameter creation tool correctly.

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 description coverage is 100% (the single 'name' parameter is documented as 1-100 characters), so the schema carries the parameter semantics. The description adds no format or constraint detail beyond it; the 'no member projects' note describes state, not the parameter. Baseline 3 is appropriate for a one-parameter tool with full schema coverage.

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 ('Creates a portfolio') and immediately disambiguates it from the sibling add_portfolio_projects by declaring the initial state ('Starts with no member projects'). An agent can distinguish this from list_portfolios, get_portfolio, delete_portfolio and rename_portfolio without opening the schema.

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?

Explicitly routes the agent to the follow-up tool ('use add_portfolio_projects next'), which is the natural workflow after creation. It does not state exclusions or prerequisites (e.g. naming collisions, uniqueness constraints), so it falls short of a full when/when-not specification.

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