SimVoro — eSIM and SMS Public Catalog

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

The annotations already declare this to be a read-only, idempotent, non-destructive lookup against a closed data source. Beyond that, the description discloses the important limitation that the list is public and generic, so country/carrier variants still require separate verification, which materially shapes how an agent should interpret a positive result. It stops short of describing the response shape or the coverage of the underlying list.

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?

One compact sentence with the primary purpose front-loaded and the caveat trailing as a qualifier; there is no filler. The trailing caveat is terse to the point that 'verification' is left slightly undefined, which is the only structural weakness.

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?

For a single-parameter read-only lookup with no output schema and safety fully covered by annotations, the definition is close to adequate, but it omits both the expected input form for 'model' and how a compatibility result should be interpreted. Those gaps matter because the tool's whole value is the yes/no outcome.

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 single parameter 'model' has 0% schema description coverage, so the description carries the full burden and fails to do so. It never states what form the model should take (marketing name, model number, manufacturer prefix) or what happens for ambiguous inputs, leaving the only required parameter effectively undocumented.

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?

The description names a specific verb and resource: 'Check SimVoro's public device compatibility list'. It is clearly distinguishable from the sibling tools (SMS pricing, service listing, travel eSIM destinations and plans), though it never explicitly contrasts itself with any of them, which keeps it short of a 5.

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 scope of the check is stated, and the caveat that 'country/carrier variants still require verification' hints at when the result is insufficient. However, there is no explicit when-to-use instruction or mention of what to do instead when the model is absent or a variant is involved.

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 readOnlyHint, idempotentHint, destructiveHint=false and closed-world scope, so the safety profile is covered. The description adds that results are "published" and "possibly changing", warning the agent that prices are volatile, but it says nothing about pagination, the meaning of the 25-item cap, or freshness/caching.

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?

There is only one sentence and it is front-loaded with the action, so nothing is padded. The semicolon-compressed, comma-heavy clause ("published, possibly changing country/operator prices") borders on ungrammatical and costs more clarity than the brevity saves.

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?

With three parameters, zero schema descriptions, and no output schema, the description should at minimum explain what `service` selects and what shape the price options take. Neither is present, so an agent must guess both the required input's role and the response structure.

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 0%, so the description carries the full burden and does not meet it: `service` (required), `limit`, and the slug pattern are unexplained. It mentions country and operator, but "operator" is not even a parameter, which can mislead an agent into expecting to filter by operator.

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?

The verb "Browse" and resource "country/operator prices and public availability" give a rough sense of a read-only catalog lookup, but the phrasing never states plainly that it returns SMS activation price options for a given service, and it omits the required `service` argument. It is distinguishable from eSIM-oriented siblings only by implication.

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?

"No rental or OTP retrieval" is an explicit when-not-to-use clause, which is real guidance. However, no alternative sibling (e.g. list_sms_services for enumerating services) is named, and there is no positive statement of the situation that should select this tool over the eSIM plan tools.

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 readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description usefully adds that prices are 'indicative' and that no numbers or codes are exposed, which is real context beyond the annotations. It still omits pagination, result ordering, and any rate-limit or failure behavior expected of a browse endpoint.

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 short sentences, front-loaded with the positive capability and immediately followed by the hard scope limit. No filler or redundant restatement of the tool name.

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?

Because there is no output schema, the description's mention of names, stock, and indicative prices is valuable return-value context. However, for a filtered-list tool with two undocumented parameters and no pagination explanation, the definition leaves real gaps an agent would need to call it confidently.

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 0%: neither 'limit' nor 'query' has any description, only types, a default of 15, a maximum of 25, and a 64-character query cap. The description never mentions either parameter, so it does not compensate for the gap — an agent must guess whether 'query' matches service names, countries, or something else.

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?

Specific verb-plus-resource: 'Look up publicly listed SMS service names, stock and indicative prices.' It also bounds scope by stating what is not returned (numbers, verification codes), which separates it from a number-provisioning tool. It does not name or contrast with any sibling such as get_sms_price_options, so sibling differentiation is left implicit.

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?

There is no explicit when-to-use or when-not-to-use guidance. The description never says whether this is the discovery step before get_sms_price_options, or when a query filter should be applied instead of listing everything. Only the negative scope statement hints at boundary conditions.

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 cover the safety profile (readOnly, idempotent, non-destructive, closed-world). The description adds two genuinely useful behavioral facts beyond that: the data is 'live' and the prices are 'indicative public starting prices', warning the agent not to treat them as exact quotes. It does not describe pagination behavior, how many results come back by default, or ordering.

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 no filler; the resource and the price caveat are both stated up front. Nothing is redundant or padded.

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?

For a two-parameter discovery tool with no output schema and no parameter documentation, the description should explain what a 'destination' result contains and how query/limit shape it. Instead it leaves filtering, page size, and result shape entirely unspecified, so an agent cannot confidently choose arguments.

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 0% for both parameters, so the description must compensate and does not. It never mentions the 'query' filter (what it matches: country, region, destination name?) or the 'limit' cap of 1-25 with a default of 15, leaving the agent to infer semantics from bare property names.

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: 'Browse live SimVoro travel eSIM destinations' plus their starting prices. An agent can distinguish this from search_travel_esim_plans (plans) and check_esim_device_compatibility (device check), though the description never explicitly contrasts with those siblings.

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?

No when-to-use guidance and no mention of alternatives such as search_travel_esim_plans. 'Browse' implies a discovery/browse scenario, but nothing states when this tool is preferred over searching plans or when it should not be used.

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 readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so the safety and idempotency profile is fully covered structurally. The description adds only two behavioral facts beyond that: results are limited to 'public sellable' plans, and purchasing is out of scope. It says nothing about result ordering, pagination, or what is returned when no plans match.

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 short, front-loaded sentences with no filler or redundancy. The brevity comes at some cost to completeness, but nothing unnecessary is present.

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 carries the burden of indicating what comes back, yet it never says the response is a list of plans with prices. Combined with the undocumented filter parameters and the unstated destination format, an agent cannot confidently construct a call beyond the required destination string.

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 0% and the description only clarifies that filtering is 'by destination'. It does not explain the destination slug format (enforced by a regex pattern), nor does it mention the three optional filter parameters limit, min_data_gb and min_validity_days, which are entirely undocumented in both schema and description.

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?

The description names a clear verb and resource ('Search public sellable eSIM plans and prices') scoped by destination, which is more specific than the title. It does not explicitly distinguish itself from the sibling list_travel_esim_destinations, so an agent must infer that this one returns plans/prices while the sibling returns destinations.

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 sentence 'Purchase happens on the SimVoro website' implies this tool is browse-only and that no transaction can be completed here, which is useful implied usage. However, there is no explicit statement of when to use this versus list_travel_esim_destinations or check_esim_device_compatibility, and no prerequisites or exclusions are given.

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