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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds real value beyond them by disclosing the return shape (two top-level sections) and the subtle behavior that `include` is applied only to the book request — a detail 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?

A single sentence with no filler; the identifying constraint ('by id') and the response structure are front-loaded, and every clause carries information about what comes back.

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 explaining return values and it does so at the section level, which is the key thing an agent needs. It could go slightly further on what `include` section names are valid or what closed positions/holdings look like, but for a single-entity read tool this is close to sufficient.

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%, so the schema already documents id, sort, limit, include and include_dust, making baseline 3 appropriate. The description contributes one genuine clarification (include applies only to the book) but says nothing about sort, limit semantics or dust handling beyond what the schema states.

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?

Names a specific verb+resource ('One syndicate by id') and enumerates the two response facets ('public page ... under `syndicate`' and 'book ... under `book`'), which cleanly separates it from list_syndicates in the sibling set. It stops short of naming the sibling as an alternative, but the singular-vs-list distinction is unambiguous.

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?

Usage is implied by the singular fetch and the id parameter, and the schema note points to list_syndicates as the source of ids, but the description itself gives no explicit when-to-use or when-not guidance against list_syndicates or get_trader.

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