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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds essentially nothing beyond that — 'RETURNS: PRISMA 流程图' merely restates the tool name and gives no indication of output format (image, SVG, Mermaid, table) or whether a figure file is written.

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?

It is short and the use-case clause is front-loaded, which is good. However, the ALIASES block is keyword stuffing for search rather than guidance, and the bilingual duplication plus a content-free 'RETURNS' line adds characters without adding 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?

For a figure-generating tool with four optional parameters and no output schema, the description leaves the key question unanswered: what the agent gets back and in what format. With zero required parameters, guidance on which counts produce a complete diagram versus a partial one would also matter.

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 all four parameters (title, records_screened, studies_included, records_identified) are documented in the schema itself. The description contributes no additional semantics, such as how counts should relate or what happens when a field is omitted, so the 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?

The description names the concrete artifact (PRISMA flow diagram) and its domain (literature screening for systematic reviews / meta-analyses), which is enough to tell it apart from data-analysis siblings. It stops short of stating the verb (generate/build), so the action is inferred from the title rather than stated.

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 'USE WHEN' clause gives an explicit triggering condition: PRISMA screening flow for systematic reviews or meta-analyses. It does not name an alternative or exclusion (e.g., consort_flowchart for trial reporting), so the agent must infer the boundary itself.

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