xlsx_post_slack

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

Discloses the 3-step upload flow, 10k/month free tier cap, and token handling options (environment vs argument). Annotations already indicate destructive (destructiveHint=true) and non-idempotent, but description adds operational context beyond annotations.

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?

Purpose is front-loaded, but description is somewhat lengthy with multiple paragraphs. Could be more concise without losing clarity.

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 6 parameters, no output schema, and 0% schema coverage, description covers usage and constraints but lacks parameter-level detail. Adequate for basic use but incomplete for nuanced decisions.

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 coverage 0% (no parameter descriptions in schema). Description explains 'message' as optional, but does not detail file_b64, filename, workbook_handle, or channel format. Only partially compensates for missing schema descriptions.

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?

Description clearly states 'upload a local .xlsx file to a Slack channel as a file attachment, with an optional accompanying message', which is a specific verb+resource. Distinct from siblings like xlsx_post_teams.

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?

Explicit 'USE WHEN' and 'DO NOT USE WHEN' sections with examples ('post this workbook to #channel') and alternatives (reading from Slack is Manual-Mode-Detector pattern). Covers token prerequisites.

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