Trace taps on a link

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

Annotations already declare readOnly/idempotent/non-destructive, so the bar is lower, but the description still adds real value: it discloses that the simulation records nothing, that the token path reads from the straitlink.in demo rather than the caller's own links, and that the output is one row per channel. It omits auth requirements and behavior when multiple of slug/url/token are supplied.

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?

Two sentences, front-loaded with the purpose, then the two modes in parallel structure. The parenthetical channel list is long but earns its place by communicating the breadth of the simulation, and no sentence is filler.

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, yet the description compensates by describing the return shape (one row per channel with decision, destination, and reason) and by explaining both input modes and their data sources. What remains unstated — mutual exclusivity of the params and error behavior — is minor for a read-only tool whose annotations cover the safety profile.

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 67% and both slug and token already carry descriptions, so the schema does most of the work. The description adds the useful framing that slug/url select the simulation path while token selects the live-trace path and corresponds to the 'st' value of a demo link, but says nothing about the undocumented 'url' parameter or precedence among the three optional params.

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 ('Explain where taps on a link go') and cleanly splits the tool into two distinct modes: a channel-walk simulation from a slug/url, and a read of a real Live Tap Trace from a token. It does not, however, differentiate itself from the sibling 'simulate_tap', which appears to cover adjacent ground, leaving the agent to infer the boundary.

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 routes between input modes ('With slug or url: ...' vs 'With token: ...') and gives the key selection signal that the token form is for a demo trace. It also clarifies the simulation is non-recording, distinguishing it from inspecting real traffic. It stops short of naming when to prefer this over simulate_tap or list_taps.

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