StackerScan

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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is covered. The description adds only the word 'latest', hinting at freshness but disclosing nothing about caching windows, refresh cadence, or whether the premium is computed from live spot data.

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 tight sentence with no redundant or padded content. It front-loads the primary output (the premium multiple) before the derived value.

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 schema covers the single parameter. What is missing is routing context against sibling tools that also expose premium or price data, which an agent would need to pick this tool 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?

Schema description coverage is 100%: the single optional 'base' parameter is fully documented in the schema, including its default of USD and a pointer to the currency catalog. The description adds no parameter meaning beyond that, 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?

The description names a specific resource and its two outputs: the Goldback premium multiple over gold content and the derived exchange rate. It is a noun phrase rather than a verb+resource, and it does not distinguish itself from the sibling get_observed_premiums, which also concerns premiums, leaving some ambiguity about which premium figure is which.

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, no prerequisites, and no mention of alternatives such as get_observed_premiums or get_spot_prices, despite those siblings appearing to overlap conceptually. The agent is left to infer selection criteria entirely.

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 establish readOnlyHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is covered. The description adds genuine interpretive context by disclosing the data source (marketplace listings) and the aggregation method (rolling, fine-metal-weighted median of asking prices), but says nothing about pagination via the cursor, data freshness, or rate limits.

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 dense sentence with no filler, front-loading the metric definition. It is slightly list-heavy at the tail, but every clause (weighting, median, source) carries interpretive value.

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 an output schema present, return values need no explanation, and annotations cover the safety profile; the methodology sentence completes the picture of what the numbers mean. The main gap is pagination/continuation behavior implied only by the cursor parameter.

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 100%, and every parameter (metal enum, query, limit, cursor) is documented in the schema itself, so the baseline is 3. The description adds no additional parameter meaning beyond listing the metal values, which the enum already provides.

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 resource (rolling fine-metal-weighted median asking premiums) and enumerates the covered metals, so an agent can distinguish it from get_spot_prices and get_price_history. It is clear about what is returned, though the verb is only implied by the tool name rather than stated.

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 when-to-use guidance: nothing says to call this instead of get_spot_prices when the agent needs a markup over spot, nor any mention of prerequisites or the relationship to the spot-price tools. Usage must be inferred entirely from the name and the word 'premiums'.

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, destructiveHint=false and openWorldHint=true, so the safety profile is covered by structured data. The description adds the daily cadence and single-metal scoping, but says nothing about ordering, rate limits, or how the cursor/results relate to each other beyond what the schema already documents.

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 resource and scope appear immediately. It is arguably too terse for a six-parameter tool with pagination and format modes, but nothing in it is wasted.

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 shape needn't be described, and annotations cover the read-only profile. However, for a paginated 6-parameter tool, the description omits result ordering, the default window behavior, and any routing against sibling price tools, leaving an agent to infer more than it should.

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 83% and the schema documents base, days, limit, cursor, format, and the metal enum thoroughly. The description only reinforces the single-metal selection ('one metal or the Goldback'), adding marginal value over the schema, so it sits at the baseline for high coverage.

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 ('Daily historical series') and scopes it to 'one metal or the Goldback,' so the agent understands it returns one time series rather than a batch quote. It does not name a sibling (e.g. get_spot_prices) to draw the live-vs-historical line explicitly, so it falls short of full sibling differentiation.

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?

'for charting' implies the intended use case and 'Daily historical series' implicitly contrasts with live spot pricing, but no alternative tool is named and there is no when-not guidance. 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 declare readOnlyHint, openWorldHint and destructiveHint=false, so the safety profile is covered. The description adds only the temporality detail (current plus previous session) and currency/unit flexibility; it says nothing about freshness guarantees, network dependency despite openWorld, or failure modes.

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 well-formed sentence, front-loaded with what is returned, with no filler or redundancy. Every clause carries 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 to cover the return shape and annotations cover the safety profile, so the description only needs to frame scope — which it does. It stops just short of explicitly routing the agent away from the neighboring history and Goldback tools.

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 100%, so base, unit and metals are fully documented in the schema, including defaults and the Goldback exclusion. The description restates the currency and unit concepts but adds no syntax or constraint 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 (retrieves spot prices) and resource, and enumerates the covered metals, currency and unit options. The 'current and previous-session' framing implicitly separates it from get_price_history, but it never names that sibling, so the differentiation is left to inference.

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 only implied: 'current and previous-session' suggests this is for latest pricing rather than a time series, but there is no explicit when-to-use, when-not-to-use, or pointer to get_price_history / get_goldback_rate as alternatives. An agent must infer the routing.

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, openWorldHint=true and destructiveHint=false, so safety is covered. The description adds real context beyond that: the list is 'live' (dynamic, not a frozen constant) and its contents are ISO 4217 fiat plus metal codes, which tells the agent what kind of values to expect.

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 that names the resource first and its scope second, with no filler. Every clause carries 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?

For a simple read-only catalog tool with an output schema covering return values and annotations covering safety, the description supplies what is needed: what the list contains and what it is for. Only the pagination/limit behavior is left entirely to the schema, a minor gap.

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 cursor are documented, limit is not), so the schema carries most of the parameter burden. The description adds no syntax or filtering detail for limit/query/cursor, and its reference to `currency`/`base` parameters concerns other tools rather than this tool's inputs — baseline 3 is 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 and resource (list of supported currency codes) and defines the resource precisely as the set of values accepted by any `currency`/`base` parameter, which cleanly separates it from the pricing siblings (get_spot_prices, get_goldback_rate). An agent can tell this is a catalog lookup, not a rate fetch, without opening the schema.

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?

Framing the list as 'every `currency`/`base` parameter accepts' tells the agent exactly when to reach for it — to validate or discover valid code values before a pricing call. It stops short of an explicit when-not or a named alternative, but the intended usage is unambiguous.

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