send_contact

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

Annotations already declare readOnlyHint=false, openWorldHint=true, idempotentHint=false, and destructiveHint=false, so the write/network profile is covered. The description adds nothing beyond that — it does not mention that a message is created in the target chat, that it is not idempotent (repeated calls post duplicate contacts), or that content-protection and notification options exist.

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 single sentence is front-loaded and free of padding, so there is no waste to trim. The problem is the opposite of verbosity — it is under-specified for a tool with 17 parameters, so brevity here buys nothing.

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 17-parameter Telegram send operation with 29% schema coverage and no output schema, a four-word description leaves the agent without the targeting, formatting, or threading information it needs to call the tool correctly. Complexity is far out of proportion to what is documented.

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 only 29% across 17 parameters, so the description carries the burden and fails to. It only hints at the required contact fields (phone_number, first_name) and says nothing about chat_id targeting, the optional vcard string, reply_markup, business_connection_id, or protect_content.

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?

"Send a phone contact" names a verb and a resource, so an agent can tell it sends contact information rather than text or media. But it does not distinguish it from near-neighbors like send_location, send_venue, or send_invoice, and never says the contact goes to a chat, which is the actual scope of the operation.

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?

There is no when-to-use guidance at all: nothing says to pick this over send_location or send_venue, nothing about prerequisites such as needing a target chat or business connection, and no exclusions. The agent must infer the selection rule from the tool name alone.

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