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

Beyond the annotations (readOnlyHint=false, idempotentHint=false, destructiveHint=false, openWorldHint=true) the description adds auth/role requirements, the 5-minute PUT URL TTL, that the host uploads local bytes with the same MCP credentials (no public link), that publishing happens immediately on HTTP success, that slides/files are announced in the activity group, and PUBLIC vs REGISTERED reachability. It even prohibits fabricating success — rich behavioral context the annotations cannot carry.

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?

Front-loaded with a bracketed scope tag, then ordered by the call sequence (preview → confirmation → PUT → publish semantics → caution), so every clause earns its place. It is dense, single-block prose with heavy semicolon chaining and could be split for scanning, but there is no filler.

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 9-parameter, 7-required, no-output-schema mutation flow, the description covers authentication, the confirmation gate, credential source, URL TTL, side effects and visibility semantics — enough to drive the tool correctly. It omits file-limit/checksum expectations (only hinted via get_agent_file_limits in the schema) and error-handling behavior, which would have made it fully complete.

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?

With only 33% schema description coverage, the description does real work: it defines the preview/previewHash interplay (undocumented in schema), the meaning of PUBLIC vs REGISTERED visibility, and ties kind implicitly to 讲义/文件. It does not explain activityRef or the SLIDES/FILE/PHOTO enum values and does not repeat the checksum/size constraints, so it improves on but does not fully cover the schema gap.

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 a specific verb+resource (prepare a private organizer material upload, then publish) and states the scope with 【需登录·主办方·对外】. It fully explains the two-phase preview→PUT-address flow, but never names or contrasts the near-identical siblings prepare_activity_photo_upload / prepare_signup_file_upload / add_activity_material, and kind includes PHOTO even though the text only mentions 讲义/文件, leaving role overlap to inference.

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?

It explicitly states the default (preview=true), the exact condition for the second call (show activity, filename, size and visibility, get confirmation, then same params + previewHash, preview=false), and the boundary that preparing is not publishing. That is a complete when/when-not sequence with no inference required.

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