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Compare databases

compare_databases

Read-onlyIdempotent

Instructions

Compare lookup answers in two loaded databases within a CIDR, for example before and after an update. Returns paginated added, removed, and changed address ranges. Equal answers with different network boundaries are unchanged. Pages scan at most 10,000 segments and can contain no changes while has_more is true. Continue until has_more is false.

Input Schema

Name	Required	Description
`network`	Yes	CIDR to compare. Use an IPv4 prefix length of 8 or greater, or a native IPv6 prefix length of 32 or greater. Repeat on each page.
`max_results`	No	Maximum changed address ranges to return on this page.
`new_database`	Yes	Comparison database's exact filename from list_databases. Supplies the after values. Both databases must be loaded.
`old_database`	Yes	Baseline database's exact filename from list_databases. Supplies the before values.
`resume_token`	No	Token from the previous page. Omit on the first request. Repeat both database names and network. If either loaded database changed, start a new comparison.

Output Schema

Name	Required	Description
`changes`	Yes
`has_more`	Yes
`resume_token`	Yes
`scanned_segments`	Yes	Address segments examined on this page, including unchanged segments. Not cumulative across pages.

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv0.4.0Oct 22, 2026

addedOutput schema / properties / scanned_segments / description

Added value: +"Address segments examined on this page, including unchanged segments. Not cumulative across pages."

Changed5 schema fields changedv0.3.1Oct 18, 2026

addedInput schema / properties / max_results / description

Added value: +"Maximum changed address ranges to return on this page."

changedInput schema / properties / network / description

Previous value: -"IPv4 /8 or smaller, or IPv6 /32 or smaller"New value: +"CIDR to compare. Use an IPv4 prefix length of 8 or greater, or a native IPv6 prefix length of 32 or greater. Repeat on each page."

addedInput schema / properties / new_database / description

Added value: +"Comparison database's exact filename from list_databases. Supplies the after values. Both databases must be loaded."

addedInput schema / properties / old_database / description

Added value: +"Baseline database's exact filename from list_databases. Supplies the before values."

addedInput schema / properties / resume_token / description

Added value: +"Token from the previous page. Omit on the first request. Repeat both database names and network. If either loaded database changed, start a new comparison."

First observedv0.1.0Oct 18, 2026

TDQS

A4.3/5.0

Behavior5/5

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

Adds genuinely non-obvious behavior beyond the annotations: equal answers with different network boundaries count as unchanged, pages scan at most 10,000 segments, and a page can legitimately be empty while has_more is true. These are exactly the traits that prevent an agent from stopping early or misreading an empty page as completion.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Five compact sentences with the core action front-loaded, followed by output shape, then the subtle equivalence rule and paging caveats. No filler and nothing repeated from the schema.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With annotations covering the safety profile and an output schema covering return values, the description is complete: it supplies the scanning bound, the empty-page edge case, and the termination condition that the structured fields do not express. An agent can call this correctly and paginate it safely from the description alone.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so all five parameters are already documented in the schema, including the resume-token workflow and the filename requirements. The description reinforces the paging discipline (repeat params, keep going while has_more) but adds no parameter-level detail the schema lacks, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource pair: 'Compare lookup answers in two loaded databases within a CIDR', including the motivating scenario (before/after an update) and the output shape (added/removed/changed ranges). It is clearly a diff operation rather than another lookup, so it is distinguishable from siblings like lookup_network, though it never names an alternative explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives a concrete use context ('for example before and after an update') and a precise paging protocol ('Continue until has_more is false'). It does not state exclusions or point to a sibling for the single-database case, so it stops short of a 5.

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

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