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

Annotations already declare readOnly, idempotent and non-destructive. The description adds the non-obvious point that no provider systems are contacted, which qualifies the openWorldHint and tells the agent this is fast and cannot fail on network or availability.

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?

A single front-loaded sentence with zero filler; the behavioral caveat is packed into the same clause rather than padding the definition.

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?

An output schema exists, so the return shape ('providers and their status') need not be spelled out. For a no-parameter read-only tool the description covers everything needed to call it correctly.

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?

The tool takes no parameters and the schema is trivially complete, so there is nothing for the description to clarify. Baseline 4 applies to zero-parameter tools.

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 configured journey providers and their status'), and the title narrows it to Italian bus providers. It implicitly separates configuration introspection from the sibling search tools, though it never names them.

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?

The phrase 'without contacting provider systems' implies this is a cheap local config read, useful for checking what is configured before a search. However, it never explicitly says when to call this versus search_journeys or search_locations.

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

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

Annotations already declare readOnly, idempotent, open-world, non-destructive, so the safety profile is covered. The description adds genuinely useful context beyond that: results are informational and include official provider links for manual continuation, making clear the tool does not book or transact.

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 short sentences, front-loaded with the action, followed by the prerequisite and the result shape. No filler or redundancy.

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?

An output schema exists, so return values need not be explained, and the description still notes the useful link payload. Combined with annotations and a 57%-covered schema, only minor gaps remain (passenger/limit semantics, date validity), which the schema largely carries.

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 57%, with origin/destination/date already documented in the schema. The description reinforces the origin/destination format convention but says nothing about provider, adults, children, or limit, so it adds only marginal meaning over the structured fields.

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 ("Search one-way journeys") and the title narrows it to Italian bus journeys. It implicitly distinguishes itself from search_locations by naming that sibling as the source of valid origin/destination values, though it does not explicitly contrast with list_providers.

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 a clear prerequisite: origin/destination must be IDs or exact names returned by search_locations, which tells the agent to call that tool first. There are no explicit exclusions or when-not-to-use conditions, but the calling context is unambiguous.

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

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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so the safety profile is covered. The description adds genuinely new behavioral context: this is a prerequisite step whose results must be fed into search_journeys as an ID or exact name, which is the key constraint an agent needs. It does not mention partial-match semantics or result cap behavior, so it stops short of full transparency.

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, zero filler, with the purpose front-loaded and the workflow instruction second. Every clause carries actionable 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?

An output schema exists, so return-format explanation is unnecessary, and the description covers purpose plus the chaining dependency. It could do slightly more for the provider/limit parameters, but nothing critical to a correct call 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 coverage is 67% — query and provider are documented inline, but limit is not. The description adds no parameter-level detail (no mention of limit, provider omission, or matching rules), so it does not compensate for the uncovered parameter. Baseline 3 applies when the schema carries most of the load.

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 (find location IDs and exact names), and the emphasis on IDs/exact names distinguishes it from search_journeys, which returns trips rather than locations. It never names list_providers as a related lookup, so sibling differentiation is partial rather than complete.

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?

'Call this before search_journeys' gives an explicit ordering constraint and tells the agent how to consume the output (reuse an ID or exact name). What's missing is guidance on the provider parameter — e.g., that list_providers supplies valid provider IDs — so one branch of usage is left implicit.

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