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

Annotations already mark the tool as non-read-only and non-idempotent. The description adds meaningful context by clarifying that it sends an external communication on behalf of the user and requires prior user confirmation. It does not cover failure/success behavior, but that is a minor 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?

The English portion is compact and front-loaded with the action, followed by the usage condition. The Bulgarian repetition is somewhat redundant for an agent-facing description but does not hurt 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?

For a straightforward send action with flat parameters and no output schema, the description covers purpose, trigger, and optional parameters. It could mention the expected return/confirmation, but the omission is not blocking.

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 80%, so most parameters are already documented in the schema. The description adds the explicit optionality of phone and message, but otherwise it largely restates what the schema already provides.

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 states a specific action ('Send an inquiry about one listing to its agency') with a clear resource and scope. It is immediately distinguishable from the read/search/subscribe sibling tools.

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?

The description explicitly says when to use the tool: after the user picks a property and confirms they want to contact the agency. It does not name exclusions or alternatives, but the trigger condition is specific enough to guide correct invocation.

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