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

Goes well beyond the annotations: partial-update semantics, silent re-geocoding that ignores accompanying city/state/zipcode, the side effect of route_id moving the stop, re-optimization flagging, the hard block on active routes, and the underlying POST endpoint. These are exactly the hidden behaviors an agent needs for a destructive mutation.

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 'WRITE:' and then a dense sequence of clauses, each carrying distinct operational information with no filler. Every sentence earns its place for a 23-parameter mutation tool.

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?

Covers eligibility, partial-update behavior, geocoding precedence, and side effects for a complex nested-object schema. The one remaining gap is the response: there is no output schema, and the description never says what a successful update returns (e.g., the updated stop object) or how failures on active routes surface.

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; the description adds cross-parameter precedence rules (address wins over city/state/zipcode and those are ignored) and the side effect of route_id, which the schema alone states only tersely. It does not add meaning for the remaining ~20 fields, but those are self-documented.

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 ('WRITE: change an existing stop') plus the key semantic 'only the fields you pass change', which immediately separates it from upper_create_stop and upper_update_route. An agent can identify the operation and its patch semantics 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 concrete preconditions and exclusions: 'stops on an active route cannot be edited' and the re-optimization consequence when editing on an optimized route. It also encodes when address vs city/state/zipcode apply. It stops short of naming sibling alternatives (e.g., create_stop for new stops), so it is clear context rather than full when/when-not routing.

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