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

With no annotations, the description carries the behavioral burden and does so well: it discloses cost ("Free"), default behavior (new widgets get app defaults / Modern design), merge semantics for widget_config, and an important non-obvious side effect (a second widget for the same URL updates the existing one instead of creating a duplicate). It does not mention permission/auth requirements or what the call returns (connection object vs id), which is the remaining gap.

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 core action and then organized per type, with no filler sentences. The telegraphic style (arrows, semicolons, sentence fragments) is dense but every line carries a distinct rule; slightly more structure would make the type-by-type rules easier to scan.

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 7-parameter, nested-object tool with no annotations and no output schema, the description covers the ambiguous decisions: which type to pick, which params matter per type, what happens on duplicate URL, and the follow-up call for embedding. What it lacks is the return value and any error/permission behavior, though the rich schema absorbs most of the parameter burden.

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 is 57% with heavy nested objects, so the description must compensate, and it does for the highest-value parameter semantics: it says website_url is required specifically for WEBSITE_WIDGET, optional for PRESENTATION_WIDGET, and unnecessary for WEBSITE_BUTTON, and it constrains design/voice settings by scenario. It adds little on the config sub-objects beyond what the schema already documents, so it is not a 5.

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 the operation (add a channel/connection to an agent) and then spells out what each of the five enum types produces. It explicitly routes away from siblings (GOOGLE_MEET → connect_google_meet, PHONE_CALL → setup_phone_agent, Telegram → connect_telegram_bot, WhatsApp → connect_whatsapp_account), so an agent can tell this apart from every adjacent tool without opening a 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?

Gives per-type when-to-use rules and named alternatives for four channel types, plus the required follow-up step (get_widget_embed_code) and the styling split between WEBSITE_WIDGET and WEBSITE_BUTTON. It also states the interactive-card prerequisite (design "modern" in chat, screen_cards=true in voice), which is genuine decision guidance rather than description of the payload.

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