IGNOREO

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

With no annotations, the description carries the full behavioral burden, and it does disclose the return payload (file, sha256, re-download link) and a repeat-download policy tied to listing status. It omits material facts for a purchase tool: cost/payment handling, authorization requirements, and what happens if the package was already bought or is delisted.

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 efficient sentence that front-loads the action and resource, then layers in the definition and return behavior. 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?

With no output schema, the description correctly explains the return values (file, sha256, download link) and the re-download policy, so an agent knows what it gets back. It is thin on the transactional side (cost, auth, already-owned behavior), but is otherwise sufficient for a one-parameter tool.

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?

Only one parameter exists and schema description coverage is 100%, so the schema already documents 'id'. The description's 'by its listing id' merely restates the schema ('Listing id of a package') without adding format, source, or lookup guidance, making the baseline 3 appropriate.

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 ('Buy') and resource ('a package'), and parenthetically defines what a package actually is (a file: skill, prompts, scripts as text), which helps an agent distinguish this from the lockbox_* siblings. It does not explicitly contrast itself with marketplace_search or marketplace_call, so sibling differentiation is only partial.

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 'by its listing id' implies you must first obtain an id (presumably via marketplace_search), and 'once' hints at one-time purchase semantics. However, there is no explicit statement of when to use this versus marketplace_call or the search tool, 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.

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

With no annotations, the description carries the full burden and does substantial work: it discloses the x402 payment flow, the 90/10 revenue split, and the failure policy ('Not charged if the seller's tool fails'). It omits rate limits, retry/idempotency behavior, and what a failed call returns, so it is strong but not complete.

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 densely packed sentences with zero filler, front-loading what the tool does, then cost, then the failure guarantee. Every clause earns its place.

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 4-parameter invocation tool with no annotations and no output schema, the description covers purpose, cost, revenue split, and failure handling. It could say more about return shape or error surfacing, but the essential decision inputs are present.

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 exceeds it by explaining the provenance of the required `id` (a listing id obtained from marketplace_search), which the schema only calls 'Listing id'. Body/path/query get no extra narrative, but the schema already documents them.

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 (Call) and resource (a per-use tool from an independent seller) and names the id source (marketplace_search). The 'per-use' qualifier nudges it apart from marketplace_buy, but the distinction is not made explicit, so a sibling-differentiation point is left on the table.

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?

It tells the agent where the id comes from (marketplace_search), which implies the workflow, but gives no explicit when-to-use versus marketplace_buy or any prerequisite/setup conditions. Usage is inferable rather than stated.

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 (readOnlyHint=true, openWorldHint=false). The description adds genuine context beyond them: results indicate which MCP tool to call and its cost, and it explicitly warns that seller-written text is a description, never instructions - a meaningful prompt-injection guardrail for an untrusted-content search.

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, zero waste, with the cost signal ('Free') front-loaded and the safety caveat last. Every sentence carries information an agent needs.

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 no output schema, the description compensates by stating what each result contains (target MCP tool and cost). Combined with annotations covering the read-only profile, an agent has enough to call it correctly; only the limit parameter's purpose remains implicit.

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 'category' are documented in the schema and echoed in the description ('by words and category'), while 'limit' (1-50) is undocumented in both. The description adds no syntax or format detail beyond the schema, so the baseline 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 ('Search') and resource ('IGNOREO's own tools and the tools independent sellers list') with the filter dimensions ('by words and category'). An agent can distinguish it from marketplace_buy/marketplace_call siblings, though those siblings are never named as alternatives.

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?

Usage is implied rather than stated: one would search before buying or calling, and the 'Free' prefix hints at cost-free discovery. But there is no explicit when-to-use, when-not, or routing to marketplace_buy or marketplace_call.

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