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

Goes well beyond the annotations: it discloses that email/phone are SHA-256 hashed locally, that confirm=false previews while confirm=true uploads, that order_id prevents duplicates, and it states the dependency (action must be 'Import from clicks' or have enhanced conversions enabled). With destructiveHint already given by annotations, this added context is meaningful.

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 the purpose before mechanics, and bullets/examples keep the format guidance scannable. It is long, but nearly every sentence (hashing, confirm semantics, required datetime) carries operational weight.

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 5-param mutation tool with annotations and an output schema, the description covers purpose, format, preconditions, and safety behavior thoroughly. The only missing pieces are brief notes on customer_id and currency_code.

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 0%, so the description must compensate, and it largely does: conversion_action meaning and constraints, the conversions row/JSON format with two concrete examples, all accepted identifier fields, datetime format and requirement, and the confirm flag semantics. It leaves customer_id and currency_code unexplained, which is the only notable 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?

States a specific verb+resource (upload offline conversions to Google Ads) and frames the business purpose (closing the CRM-to-ads loop so Smart Bidding optimizes for revenue). It is clearly distinguishable from siblings like upload_conversion_adjustments and upload_microsoft_offline_conversions.

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?

Explicitly says when to use it (a lead from an ad later became an offline sale) and routes to sibling tools (list_conversion_goals / get_conversion_tags) for obtaining conversion_action. It does not, however, contrast itself against the closely-related upload_microsoft_offline_conversions or upload_conversion_adjustments.

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