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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds valuable behavioral context: the tool auto-detects content type across videos, articles, and dynamics, and handles ambiguous IDs via automatic recognition. This exceeds annotation coverage without contradicting it.

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?

The description is a single, front-loaded sentence that names the action, the resource types, and the accepted ID forms. It contains no filler, redundant annotation repetition, or structural noise.

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?

Given the tool's complexity—multiple content types and ambiguous ID formats—the schema and description together provide rich invocation guidance, and an output schema exists so return-value explanations are unnecessary. The only minor gap is that alternative-tool routing for URL-based input is left to inference from sibling names rather than stated explicitly.

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 for content_id is 100%, and the schema already explains preferred formats, ambiguous bare-number handling, and disallowed inputs. The tool description mentions the same ID families at a higher level but adds little meaning beyond what the schema already provides, so the baseline 3 is appropriate.

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 clearly states a specific action ('自动识别并读取' / automatically identify and read) and a specific resource ('视频详情、专栏详情或动态详情'). It also distinguishes this tool from the sibling by naming the input mode (by ID) and enumerating accepted ID formats, so an agent can tell it apart from bilibili_get_content_detail_by_url without opening the 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 gives clear input-format guidance and an explicit 'do not pass links' exclusion, but it does not explicitly state when to prefer this tool over bilibili_get_content_detail_by_url or other siblings. The usage context is implied by the tool name and sibling list, but the description itself leaves alternative-tool routing implicit.

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