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

Annotations already cover safety (readOnly, idempotent, non-destructive), and the description adds substantial context beyond them: the server cannot post into the conversation so the agent must relay results, a hard cap of 20 newest matches, price reported in CZK with a verdict at match time plus a link, aggregator coverage limits, and the caveat that a car may already be sold. This is exactly the behavioral disclosure a read tool needs.

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?

Dense but front-loaded: usage trigger first, then return shape, then caveats. Five sentences all carry information, though the return-contents sentence is somewhat long and partly redundant given an output schema exists.

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?

Even though an output schema exists, the description supplies the operational caveats an agent needs to interpret results correctly (20-match cap, CZK pricing, aggregator incompleteness, possibly-sold cars, empty before confirmation). Nothing material for correct invocation or result interpretation is missing.

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 both parameters are already documented (intentCode format/pattern, since as an ISO datetime). The description restates these ('Requires the intentCode; optional since (ISO time) returns only newer matches') without adding format, timezone, or pagination nuance beyond the schema, so the baseline of 3 applies.

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+resource ('List cars found for a car watch') and immediately anchors it to the intent created by intent_publish_intent, which is a named sibling. An agent can distinguish this read tool from intent_get_intent, intent_publish_intent, and intent_withdraw_intent without opening any 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 gives the trigger: 'Use this when the user asks what AutoIsto has found for an intent created with intent_publish_intent,' and adds the precondition that no matches exist before the user confirms the intent. It does not explicitly route the agent elsewhere (e.g. to intent_get_intent for intent metadata), so it stops short of full when/when-not coverage.

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