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

Annotations already declare readOnlyHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is covered. The description adds genuinely useful non-annotation behavior: weekly refresh cadence (Friday close), the free-tier data boundary (no cost basis or P&L), and the source it mirrors. It does not state a response format, which keeps it short of a 5.

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?

Content is front-loaded: what the tool returns comes first, then the free/subscriber boundary, then cadence. It is dense but every clause except the 'mirrors closelook.net/portfolios/' line carries decision-relevant information.

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 burden of describing return values, and it does so by listing the fields returned (snapshot date, position count, top-10 holdings, headline return) and their scope (free vs subscriber). It stops short of field naming or pagination/size limits, leaving a small gap for a multi-book tool.

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%, so the baseline is 3, but the description adds real meaning by mapping human-readable book names (AI Build-Out, Hypergrowth, Global Tech 50, Rubin EW, T1, etc.) onto the slug values the schema enumerates. That mapping helps the agent choose the right slug, though it does not add format or default semantics beyond 'omit for all'.

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 resource (closelooknet's live reference portfolios) and enumerates exactly what the snapshot contains: date, position count, top-10 holdings by weight, headline return vs deposited capital. It also names the books covered, so an agent can distinguish it from siblings like get_index_snapshot or get_ranking without opening a 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?

The description implicitly scopes usage via 'exactly what the free page shows' and the subscriber-only caveat, which tells the agent this is a public-tier summary rather than full composition. However, it never states when to prefer this over sibling tools such as get_index_snapshot or get_stock_snapshot, and gives no explicit exclusions or routing guidance.

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