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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral context beyond annotations by calling it a 'Public read' and indicating the data is Mako-curated and auditable, which helps the agent understand access and provenance.

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?

Two compact sentences, with the core purpose first and the sibling distinction second. There is no redundant wording, and the parenthetical field list efficiently conveys the return contents without bloating the description.

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 zero-parameter read-only tool with an output schema present, the description fully covers purpose, access level, data provenance, and the relationship to a sibling tool. Nothing needed for correct invocation or selection 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?

The tool has zero parameters and schema description coverage is 100%, so the baseline of 4 applies. The description adds no parameter confusion and even lists output fields ('CNY trillions + source URL + as_of_month + note'), which indirectly clarifies what the no-argument call returns.

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?

The description uses a specific verb ('Read') and a specific resource ('latest Mako-curated PBoC balance-sheet publication'), then enumerates the contained fields. It also distinguishes itself from get_financial_conditions by noting the same value is embedded there, which prevents confusion among 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 description explicitly states when to use this tool ('suitable for surfacing directly when explaining the China leg of global liquidity') and names the alternative path (get_financial_conditions.pillars.global_liquidity.components.china) with the reason to prefer this tool ('direct/auditable access'). This is clear routing guidance.

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