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

Annotations cover read-only/idempotent safety, but the description adds substantial behavior beyond that: the org.project.view.all-gated hiddenProjectCount, the budget=null / costHidden=true masking rule for unreadable costs, exclusion of archived projects, and a plan-tier requirement. These are exactly the non-obvious traits an agent needs.

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?

Four dense sentences, each carrying distinct information, front-loaded with what the tool returns before the gating details. No filler or restatement of the name.

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, the description carries the return-value burden and does so: it enumerates owner, project summaries, hiddenProjectCount, and the budget/costHidden masking semantics. Nothing material for correct invocation is missing.

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 portfolioId parameter is documented in the schema as 'Portfolio id'. The description adds no format, source, or lookup guidance for it, 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 ('Get one portfolio with its in-scope projects') and immediately scopes the response contents. This clearly differentiates it from the plural list_portfolios and the aggregate portfolio_summary siblings.

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 singular 'one portfolio' implies single-target retrieval versus the list sibling, but the description never explicitly says when to use this over list_portfolios or portfolio_summary. The BUSINESS+ plan requirement is a useful precondition, though it's a gating constraint rather than usage guidance.

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