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UI Verify

by ai.uiverify

Fetch the actual pixels of a story image

render_diff_image
Read-only

Fetch a story's image as an INLINE image (base64 pixels, not a URL) so a vision model can look at it directly. Needs a native MCP client that renders image content; piped through raw curl it is useless (use get_diff's URLs there instead). Two ways to address it: (1) diffResultId + which for a CHANGED story - which is baseline|candidate|diff (the triptych) or before_after, the baseline and candidate SIDE BY SIDE (before on the left, after on the right) cropped to the changed region - and when a story changed in SEVERAL far-apart places, one such crop PER region stacked top to bottom, so a header-plus-footer change is two tight crops, not a page-tall image. before_after is usually what you want for a code change - it zooms to what moved instead of a full page. Get diffResultId from get_build (changedStories[].diffResultId) or get_diff. (2) a build selector (commitSha|prNumber|buildId) + storyId for ANY story's current image - the candidate if it changed this build, else its baseline. This second form is the only way to see an UNCHANGED/passed story's pixels (list them via list_build_stories status=unchanged), so you can confirm 'identical to baseline'. Errors if the image doesn't exist (a genuinely new story has no baseline, so no before_after either).

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
whichNoFor the diffResultId form: baseline|candidate|diff (one triptych image, default candidate), or before_after (baseline+candidate side by side, cropped to the change - one crop per changed region, stacked, when the change spans several places). Ignored for the storyId form.
buildIdNoResolve this exact build id.
storyIdNoWith a build selector: fetch THIS story's current image (works for unchanged stories).
prNumberNoResolve the latest build for this PR number.
commitShaNoResolve the build for this git commit SHA.
diffResultIdNoA CHANGED story's diff result id (from get_build/get_diff); pair with `which`.

Schema Changelog

Changes observed during successful MCP inspections. Dates show when Glama detected each change.

  1. First observed

TDQS

A5/5.0
Behavior5/5

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

Beyond the readOnlyHint annotation, the description discloses important behavioral traits: the output is inline base64 pixels requiring a native MCP client, images are cropped to changed regions with per-region stacking, and the tool errors when the image does not exist (e.g., a genuinely new story has no baseline). This is substantial behavioral context that the annotations alone do not provide.

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?

The description is long but densely packed with necessary information: purpose, client requirement, alternative routing, two addressing modes, crop behavior, and error conditions. It is front-loaded with the core purpose, then builds outward, and every sentence serves a distinct guidance function.

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?

Given there is no output schema, the description compensates by explaining the output form (inline base64 pixels), layout behavior (side-by-side crops, stacking), error cases, and how to obtain diffResultId from get_build/get_diff. The tool is complex with two alternative invocation forms, and the description covers both completely.

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

Parameters5/5

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

Even though schema coverage is 100%, the description adds valuable cross-parameter meaning: it explains that diffResultId pairs with which, that buildId/prNumber/commitSha act as build selectors, and that storyId works even for unchanged stories. It also clarifies the nuanced semantics of before_after (side-by-side crops stacked per changed region), which the enum alone does not convey.

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

Purpose5/5

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

The description opens with a specific verb and resource: 'Fetch a story's image as an INLINE image (base64 pixels, not a URL)' and clearly distinguishes this from get_diff by stating that get_diff's URLs should be used in a curl pipeline. It also names two concrete addressing forms, leaving no ambiguity about what the tool does.

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

Usage Guidelines5/5

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

It explicitly explains when to use this tool versus alternatives: 'piped through raw curl it is useless (use get_diff's URLs there)' and defines which addressing form to use for changed versus unchanged stories. It even recommends before_after for code changes and points to list_build_stories for unchanged stories, giving actionable routing guidance.

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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TDQS

A4.7/5.0
Disambiguation5/5

Each tool targets a distinct concern: list vs get vs pagination, build triage vs PR changeset, diff URL vs inline pixels, single-review vs bulk-accept. The descriptions explicitly call out the differences between similar-sounding tools, so an agent can reliably choose the right one.

Naming Consistency5/5

All tool names follow a consistent lowercase verb_noun pattern: get_* for single entities, list_* for collections, and review_diff/accept_build for actions. There are no mixed conventions or vague verbs.

Tool Count5/5

Nine tools fit the visual regression review workflow well: discovery, triage, pagination, image inspection, and reviewing. Each tool fills a distinct role without redundancy, and the count is in the sweet spot for an agent to keep all tool purposes in context.

Completeness5/5

The surface covers the full review lifecycle: find builds, triage changed/failed/unchanged stories, paginate, inspect diffs as URLs or inline images, review per-diff, and bulk-accept an entire build. The PR-changeset tools also cover cross-PR questions and deletion cases that would otherwise be dead ends.

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