Canada River Levels & Flood Watch MCP

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

With no annotations, the description carries the behavioral burden and does disclose useful traits: a 25-postal-code limit, sorting with rising sites first, and the returned information. However, it omits important details such as error behavior, authentication expectations beyond the token schema field, and whether results are cached or real-time.

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 compact single sentence with the key scope and return summary front-loaded after the PRO marker. It is appropriately sized, though the standalone 'PRO.' is slightly opaque and could be clearer.

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 lookup tool with no output schema and no annotations, the description gives enough to understand the basic return (nearest gauge and 24-hour change) and input limit. It remains incomplete on sibling selection, postal code formatting, and fuller response/auth behavior.

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 50%: access_token is documented in the schema, while postal_codes is not. The description partly compensates by stating the 25-postal-code limit and implying the array contains postal codes, but it does not clarify postal code format or validation.

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 states a specific resource and scope: nearest gauge and 24-hour level change for up to 25 postal codes, with rising sites first. It distinguishes itself operationally from siblings by being postal-code based, though it does not explicitly name or contrast with gauge_trend or river_levels.

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 an input constraint (up to 25 postal codes) and ordering behavior, but does not say when to use this tool instead of gauge_trend or river_levels. There are no exclusions, prerequisites, or alternative-selection guidance beyond the vague PRO marker.

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. It does disclose the 30-day lookback cap and the returned metrics (min, max, latest, 24h change, rise rate), and the leading 'PRO' hints at a paid/subscriber tier, but it never states access requirements, rate limits, cost, or error behavior for gated access.

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 terse fragments — a tier flag and a single sentence — with the resource and returned metrics front-loaded. No filler, though the standalone 'PRO.' marker is slightly cryptic as an opener.

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?

The description compensates for the absent output schema by enumerating return values, which is the key gap filler. However, with no annotations and gated access implied, it should clarify what 'PRO' entails (subscription requirement, what happens with a free token), which an agent needs to call it successfully.

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 33% (only access_token is documented), so the description must compensate. It does add meaning to 'days' by capping history at 30 days and clarifies 'station' as the subject of the query, but it leaves the units/type of days (a number, floor vs. fractional) and station identifier format ambiguous.

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 resource and operation: level/flow history for a single station, with the aggregate outputs enumerated. It implies differentiation from river_levels (current values) and flood_watch (alerts) via 'history' and 'trend', but never names the siblings 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?

Usage is implied by 'history ... up to 30 days', which suggests retrieving a time series for one station rather than current readings. There is no explicit when-to-use vs. when-not guidance and no mention of the sibling tools flood_watch or river_levels as alternatives.

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, and it does disclose several real traits: the call is free, results are real-time/latest, the search radius is capped at 25 km, and at most 3 gauges are returned. It omits what happens with an invalid or non-Canadian postal code, whether an empty result is possible in sparse areas, and the units/format of returned levels.

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 terse sentences with no filler; the 'FREE' marker and the 25 km / nearest-3 limits are front-loaded. Nothing is wasted, though the telegraphic style leaves the radius and count constraints slightly ambiguous in phrasing.

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 read tool with no output schema and no annotations, the description conveys the essentials of scope and result size but leaves the return shape undocumented — an agent cannot know field names, units, or whether flows and levels are returned together. Adequate, 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 description coverage is 0%, so the description must compensate, and it does add one meaningful fact: the postal code must be Canadian. It says nothing about format expectations (spacing, case, six-character alphanumeric), and the single parameter's required status is only visible from the schema.

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?

Names a specific resource (river/lake water levels and flows at gauges) and a specific scoping rule (within 25 km of a Canadian postal code, nearest 3). Clear enough that an agent can distinguish it from a trend or flood-alert tool by subject matter, though it never explicitly contrasts itself with flood_watch or gauge_trend.

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 or when-not-to-use guidance and no mention of the siblings flood_watch and gauge_trend, which an agent would plausibly confuse with a level-lookup tool. The only usage-adjacent signal is the constraint 'nearest 3' inside a 25 km radius, which limits results rather than guiding selection.

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