Australia FX Rates (RBA) MCP

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

With no annotations, the description carries the full burden; it does disclose two useful traits beyond the schema — the data source (latest RBA rate) and that this is a subscriber/PRO feature, which explains the access_token parameter. It says nothing about failure behavior for unlisted currencies, rate staleness/timestamping, or what a successful response returns.

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 tight sentence with the core operation front-loaded and the '(A$1 = X)' direction note earning its place. The leading 'PRO' tag is terse and slightly cryptic without context, but the overall size is appropriate.

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 3-parameter tool with no output schema, no annotations, and low schema coverage, the description leaves too much open: which currencies are 'listed', what the response contains (converted amount, rate used), and what the PRO/access_token requirement means in practice. It is not sufficient on its own for reliable invocation.

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 33%, with just access_token documented, so the description must compensate and largely does not. 'Listed currency' gestures at an allowed-value set for the currency parameter but never enumerates or explains it, and it adds nothing about amount_aud beyond the name.

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: convert AUD into another currency using the latest RBA rate. The '(A$1 = X)' clause pins down the conversion direction. It does not distinguish this from siblings fx_rate and fx_table, so an agent can't tell why it should pick convert over a raw rate lookup.

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 relative to fx_rate or fx_table, which are the obvious alternatives. The only hints are indirect: 'PRO' suggests a paid-tier requirement and 'listed currency' implies a restricted currency set, but neither is explained.

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 burden, but it does contribute real behavioral context: the data source (RBA), freshness ("Latest"), and cost ("FREE"). It stops short of disclosing return shape, update cadence, base-vs-target direction, and error behavior, which matter for a data-retrieval tool with zero annotation coverage.

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 very short fragments, no filler beyond the leading "FREE." marketing token, and the resource is stated immediately. Slightly front-loaded with cost rather than function, but essentially no waste.

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 one-parameter tool with no output schema and no annotations, the description should at minimum say what comes back and how it differs from fx_table and convert. It leaves the return shape (single number vs. column) and sibling boundary unresolved, which is the core decision an agent must make.

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 0%, so the description must compensate, and it partially does by giving concrete code examples (USD, CNY, JPY, EUR, GBP) that establish the expected 3-letter currency-code format. It does not clarify whether the supplied currency is the target or the base relative to AUD, nor what happens if AUD is passed.

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 identifies the resource as the latest RBA AUD exchange rate and implies a lookup verb, so the general intent is graspable. However, "column" is ambiguous (single rate vs. a series) and nothing distinguishes this from siblings convert or fx_table, leaving the agent to infer the boundary.

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 at all: no mention of when to prefer this over convert (likely for converted amounts) or fx_table (likely for the full table). The only usage-adjacent signal is "FREE", which speaks to cost, not 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?

With no annotations, the description carries the full behavioral burden and discloses almost nothing: it hints at a read of a 'latest' snapshot but not whether it is cached, how often the RBA table refreshes, what columns a 'full row' contains, or that access requires a paid subscription. Auth is only implied by the word 'PRO' and the access_token parameter.

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?

It is very short and front-loaded, but the compression goes too far: 'PRO' and 'F11.1' are unexplained abbreviations rather than useful shorthand. Brevity here reads as under-specification rather than economy.

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 annotations and no output schema, the description must explain what is returned and under what conditions; instead it offers a single cryptic clause. An agent would not know the currency coverage, row shape, or freshness guarantees of the result.

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?

There is a single parameter with 100% schema description coverage ('Subscriber token from /success (or Authorization: Bearer)'), so the schema already documents it fully. The description adds no additional meaning about the token or optionality, 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 resource ("Latest full RBA F11.1 FX row") but no verb, and the jargon ("PRO", "F11.1") assumes domain knowledge the agent may not have. It does not differentiate from the sibling fx_rate, which plausibly returns overlapping FX data, so an agent cannot confidently choose between them.

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 statement of when to use this tool versus fx_rate or convert, and no prerequisites or exclusions are given. The only implied guidance is the "PRO" prefix, which is not explained anywhere in the description.

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