Baby Registry – hand-picked gift ideas

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

No annotations are provided, so the description carries the full disclosure burden for a write operation, yet it says nothing about duplicate handling, what happens if the registry id is invalid, the auth/permission implications of editToken, or any response shape. The mention of required tokens is the only hint that this is an authenticated mutation, which is thin for a state-changing tool.

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, purpose first, then the parameter-selection hint, then prerequisites. Nothing is wasted and nothing important is buried.

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 an 11-parameter, unannotated mutation with no output schema and low schema coverage, the description is too thin: an agent still cannot tell whether url and asin are mutually exclusive, what searchKeywords does, or how to recover from a duplicate or invalid-token failure.

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 only 36% across 11 parameters, so the description needs to compensate. It does add real, non-schema meaning for asin (use it for /dp/ links) and implicitly its precedence over url, but leaves url, emoji, notes, title/name precedence, editToken, and searchKeywords unexplained.

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 concrete verb and resource (add an item to a baby registry/wishlist), and the word 'existing' plus the registry id implicitly separates it from create_registry and create_and_fill_registry. It stops short of naming those siblings, but the operation is unmistakable.

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 gives one real routing rule — prefer asin for tagged /dp/ links on amazon.se — which is genuine guidance. The 'Requires editToken, marketplace, locale' sentence only restates what the required array already declares, and there is no explicit statement of when to use this versus create_and_fill_registry or resolve_product.

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?

No annotations are provided, so the description carries the full disclosure burden. It usefully reveals the return payload (ownerUrl + shopUrl + editToken) and the required marketplace + locale, but says nothing about auth requirements, whether the created registry is public, or the sensitivity implication of emitting an editToken.

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?

Front-loaded verb+resource, then scope, then return values, then requirements — dense and waste-free. Every clause carries signal, though the sentence is packed enough that a bit more structure would aid scanning.

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 an 8-parameter mutation tool with no annotations and no output schema, the description covers the action, return shape, and required fields. It falls short on the three optional descriptive params and on the security/auth implications of a tool that mints an editToken, which is the kind of context an agent most needs.

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 only 25%, so the description must compensate. It maps 'ASINs/keywords/queries' to itemAsins/itemKeywords/itemQueries and flags marketplace+locale as required, but leaves ageBand, childName, and interests 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?

States a specific verb+resource: 'create a registry and fill from ASINs/keywords/queries', and the 'one-shot' framing distinguishes it from the sibling create_registry/add_registry_item (which are single-step). It doesn't explicitly name those siblings, so an agent must infer the differentiation rather than being told.

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?

'Best tool for agents building a full baby list' gives clear positive context for when to reach for this over the incremental siblings. However, it offers no exclusions (e.g., 'use create_registry if you only need an empty registry' or 'use add_registry_item to append'), leaving the boundary to inference.

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 does meaningful lifting: it declares the operation creates an empty container and enumerates the return fields (id, editToken, ownerUrl, shopUrl). However, it omits that editToken is a credential granting edit access, whether the call requires authentication, and whether repeated calls create duplicates — important gaps for an unannotated mutation.

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?

Four short, front-loaded sentences with the core action stated first and returns and prerequisites after. "Requires marketplace + locale" slightly duplicates the schema's required array, but the overall shape is efficient.

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?

Listing return fields is valuable given there is no output schema, but an agent still lacks guidance on the optional personalization parameters and on auth/duplicate behavior for a creation call. Adequate as a minimum-viable definition, not complete.

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 only 40%, and the description merely restates that marketplace and locale are required, adding no format or meaning beyond the schema's own examples. The three undocumented parameters (ageBand, childName, interests) receive no explanation anywhere, so the description fails to compensate for the coverage gap.

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?

"Create an empty baby registry / wishlist" gives a specific verb and resource, and the word "empty" implicitly separates it from the sibling create_and_fill_registry. It is clear without opening the schema, though the sibling is never named explicitly.

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?

"Start of list-building" hints at the workflow position and "Requires marketplace + locale" states prerequisites, but there is no explicit statement of when to prefer this over create_and_fill_registry or add_registry_item. The agent must infer the contrast from the word "empty".

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 disclose the key return behavior: buyUrl plus trackingTag, with affiliateUrl as a compatibility alias. It does not explain side effects, permissions, rate limits, precedence among asin/url/keywords, or failure behavior, so important behavioral context is still missing.

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 definition is a single front-loaded sentence with no wasted language. It efficiently states the resolution target, accepted inputs, marketplace scope, and primary output fields.

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 7-parameter tool with no annotations and no output schema, the description is adequate but incomplete. It names the main output fields and input alternatives, but does not cover several parameters or behavioral details needed to invoke it confidently in all cases.

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 description adds meaning for three otherwise bare inputs (asin, url, keywords) and references the selected marketplace, but schema description coverage is only 29%. It does not explain ageBand, category, the required locale semantics beyond what the schema already says, or how multiple input forms interact.

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 gives a specific verb and resource: it resolves ASIN, Amazon URL, or keywords into a curated buy URL on a selected marketplace. It is clearly not a registry or general catalog-search operation, but it does not explicitly distinguish itself from siblings such as search_catalog or search_suggest.

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 accepted input forms imply that the tool is used when an agent already has an ASIN/URL or keywords and needs a buy URL. However, there is no explicit guidance on when to use this instead of search_catalog or search_suggest, and no exclusions or prerequisites are 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?

With no annotations at all, the description carries the full burden; it does disclose the catalog's size and domain coverage, the two required inputs, and the returned fields. It omits pagination/total-count behavior despite exposing limit and offset, says nothing about empty-result behavior, and never explicitly states the operation is a read-only lookup. Adequate but with real gaps for an annotation-free tool.

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 tight sentences: purpose first, return shape second, intended use and prerequisites last. The parenthetical category list is the only slightly expendable element, but it conveys catalog breadth efficiently.

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 7-parameter search tool with no output schema, the description does tell the agent what comes back (asin + buyUrl) and what is mandatory. It leaves pagination behavior, result ordering, and total-count semantics unexplained, which matters given limit/offset 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 description coverage is 71%, below the threshold where the schema alone would suffice, so the description should compensate more. It does reinforce that marketplace and locale are required, but q, limit, offset, ageBand, and interest are only documented in the schema — the description adds no filtering or pagination semantics of its own.

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 concrete verb and resource — searching a curated baby registry catalog with a stated scope (100+ amazon.se essentials across eight categories) — and states the return shape (asin + buyUrl). It does not name the sibling tools search_suggest or resolve_product, so the agent must infer the boundary between catalog search and product resolution.

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?

"Use to pick items when building a shopping list / registry" gives a clear triggering context, and "Requires marketplace + locale" flags the two mandatory inputs. There is no explicit when-not guidance or routing to siblings (e.g. resolve_product for a specific known item, search_suggest for query autocomplete), which keeps it below a 5.

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 it does disclose one non-obvious behavior: queries get rewritten with age/category cues rather than passed through verbatim. It still omits return shape (what a 'suggestion' looks like), pagination/limit behavior, and any rate or permission constraints.

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?

Four short sentences, front-loaded with the core action and followed by behavior and prerequisites. No wasted words, though the fragments are terse enough that some clarity (e.g. return format) is sacrificed.

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?

Covered: action, a behavioral trait, a usage context, and required inputs. The residual gap is that with no output schema the description never says what comes back, and sibling differentiation is missing; given the 6-param tool with strong schema coverage, this is a modest rather than severe omission.

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 high (83%), so the parameters are largely self-documenting and baseline 3 applies. The description adds a little by tying 'age/category cues' to ageBand and interest, but doesn't clarify how those interact or what happens when they're omitted.

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 Amazon for baby registry / shopping-list ideas', plus a secondary trait (query rewriting with age/category cues). It's clear what the tool does, but it never distinguishes itself from the sibling search_catalog, so an agent can't immediately tell them apart.

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?

'Use when building a recommendation list' gives a usage context, and 'Requires marketplace + locale' flags prerequisites. However, no alternative is named — with search_catalog and resolve_product as siblings, the agent is left to infer which search path to choose.

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