List restaurants

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

Annotations already carry readOnlyHint/idempotentHint/openWorldHint/destructiveHint=false, so the safety profile is covered. The description adds non-obvious behavior beyond that: geographic 404 failure mode, and that page 1 returns a 'categories' payload used to drive the category param. It does not discuss pagination exhaustion or rate limits, hence not a 5.

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?

Three tight sentences, front-loaded with the core capability, then the sibling routing and error condition. No filler, and every clause conveys distinct information.

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?

There is no output schema, so the description usefully names the fields returned and flags the page-1 categories object. It also covers the main failure mode. The return shape is only sketched at a high level rather than itemized, which keeps it just short of complete for a 10-param, no-output-schema tool.

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 100%, so the baseline is 3 and the schema already documents each param. The description adds cross-parameter meaning the schema does not: 'categories' returned on page 1 is the source of valid values for the category param, and page 1 lists fewer vendors because page_size is partly spent on widgets.

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 ('List restaurants (or grocery stores) delivering to a point') and enumerates the returned fields (rating, delivery fee, minimum order, ETA). It also draws a boundary against tf_menu ('No dish prices'), so the agent can distinguish it from siblings 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?

Explicitly says when to use it ('browse or rank vendors'), names the alternative for dish prices (tf_menu), and states a concrete failure condition ('Returns 404 outside the served cities') plus the tool to check coverage (tf_list_cities). Both a positive and negative routing decision are given.

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