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

Annotations only establish that this is a non-read, non-destructive, open-world write. The description goes well beyond that: it discloses that omitted required fields return as errors for the agent to fill, that the call returns listing_id and public URL, that confirmation defaults on but can be disabled, that the call reaches other people, and that a scoped API key is required. This is exactly the extra context annotations don't carry.

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-loads what the tool does and what it returns, then layers error/auth/confirmation behavior. Mostly earns its sentences, though the confirmation point is restated twice ('By default you confirm each call' and 'confirm with the user before each call'), which is mildly redundant.

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 create tool with no output schema, the description covers return values (listing_id, public URL), error behavior on missing required fields, side effects (reaches other people), auth requirements, and confirmation policy. An agent has everything needed to invoke safely and interpret the response.

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 100%, so every parameter is already documented in the schema; baseline is 3. The description alludes to property details and document URLs but adds no syntax, format, or constraint detail beyond what the schema states.

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 and resource ('New sale or lease listing on the marketplace... Creates a listing in your account') and distinguishes itself from read/update siblings like crexi_get_listing and crexi_update_listing_status. An agent can tell exactly what the tool produces without opening the 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 clear operational context: it is used to create a listing from property details and document URLs, requires confirmation before each call, and needs an API key with app access. It does not explicitly name an alternative or a when-not condition, so it stops short of a 5.

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