vapi_market_player_all_listings

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

Since no annotations are provided, the description carries the full disclosure responsibility. It transparently states that the tool does not auto-fetch continuation pages, has a 100-row and 256 KiB local limit, reports truncation in text and metadata, refuses oversized records without partial fields, and that the route name does not guarantee completeness. It also clarifies that declared filters are forwarded without implying their effectiveness. This is unusually detailed behavioral disclosure.

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?

The description front-loads the purpose then adds a set of distinct behavioral constraints in a mostly compact form. Some phrases are vague (e.g., 'Required inputs reflect tool policy as well as measured upstream requirements') and add limited clarity, but each sentence contributes a separate piece of information. Overall it is appropriately sized and reasonably structured.

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 tool with no output schema and no annotations, the description covers pagination, truncation, size limits, and error handling. It also warns about completeness limitations. However, it does not explain what 'listing items' means precisely, nor the expected format of the 'player' parameter, which leaves some ambiguity for correct invocation. Core behavior is well covered, so 4 is warranted.

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 only parameter 'player' is not described except as a schema string with minLength 1. Schema description coverage is 0%, so the description must compensate, but it does not explain what the parameter represents (e.g., account name, ID, username) or any expected value. Moreover, the statement 'Other declared filters are forwarded as supplied' is misleading because the schema has additionalProperties: false and only 'player' is defined, so there are no other filters to forward.

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 opens with 'Read account listing items across assets', which gives a specific verb and resource, and it explicitly notes the mixed asset types in the response (PACKS, CONSUMABLES, SKINS, MUSIC). It distinguishes itself from likely more specific market tools by emphasizing 'across assets', though it does not explicitly name sibling tools or state what makes it different from vapi_market_player_listings.

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 guidance on when to choose this tool over alternatives. The description provides caveats about truncation and completeness but does not say 'use this when...' or 'for X use the other tool'. No sibling is referenced, and no exclusions or alternatives are given, leaving the selection process to inference.

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